MIC-KEY Extension Sets Explained: Continuous vs. Bolus Feeding & ENFit Compatibility

If you use an Avanos MIC-KEY feeding tube, choosing the correct extension set is essential for connecting the low-profile button to compatible enteral feeding equipment.

Unlike traditional gastrostomy tubes with longer external tubing, a MIC-KEY low-profile G-tube button sits close to the skin. A removable extension set provides the connection needed for prescribed feeding, hydration, or medication administration.

However, not all MIC-KEY extension sets are the same.

Avanos manufactures continuous feeding extension sets, bolus feeding extension sets, and different ENFit and legacy connector configurations. These products vary in tubing length, connector design, and manufacturer part number.

This guide explains the differences between MIC-KEY extension sets, how ENFit connectors work, and what patients, caregivers, and healthcare purchasing departments should verify before ordering replacement feeding tube supplies.

What Is a MIC-KEY Extension Set?

A MIC-KEY extension set is a removable length of medical tubing designed to connect a compatible MIC-KEY low-profile feeding tube to an enteral feeding administration system.

The extension set connects to the button using the manufacturer's specified connection mechanism, such as the SECUR-LOK connector used on many Avanos MIC-KEY products.

Depending on the model, the opposite end may include an ENFit connector, a legacy catheter-tip connection, or another enteral feeding connection.

Some extension sets also include a Y-port, medication access port, or tubing clamp.

The exact configuration depends on the manufacturer's part number.

Why Do MIC-KEY Buttons Need Extension Sets?

A low-profile MIC-KEY button has a compact external design, rather than a long section of permanently attached feeding tubing.

The removable extension set allows the prescribed feeding equipment to be connected when needed.

The extension set is a separate accessory and may have its own replacement requirements.

Continuous vs. Bolus MIC-KEY Extension Sets

One of the most common questions is whether to purchase a continuous feeding extension set or a bolus feeding extension set.

Both are designed for compatible enteral feeding applications, but their connection configurations can differ.

MIC-KEY Continuous Feeding Extension Sets

Avanos MIC-KEY continuous feeding extension sets commonly feature a right-angle SECUR-LOK connection at the button and a two-port Y-connector configuration.

Depending on the model, they may also include an ENFit connector and tubing clamp.

These sets are designed for use with compatible feeding arrangements as specified in the manufacturer's instructions.

Common features include:

• Right-angle SECUR-LOK button connector

• Two-port Y-connector on selected models

• ENFit or legacy enteral connector configurations

• Different tubing lengths

• Integrated clamp on applicable models

MIC-KEY Bolus Feeding Extension Sets

MIC-KEY bolus extension sets are designed for compatible intermittent feeding arrangements.

Avanos offers straight and right-angle SECUR-LOK bolus configurations, depending on the product.

Some models include an ENFit bolus connector, while legacy versions may use a catheter-tip connection.

Continuous vs. Bolus Extension Set Comparison

Feature	Continuous Extension Set	Bolus Extension Set
Typical Configuration	Often two-port Y-connector	Often single-port
Button Connection	Commonly right-angle SECUR-LOK	Straight or right-angle SECUR-LOK
ENFit Options	Available	Available
Legacy Connector Options	Available on selected models	Available on selected models
Tubing Length	Varies by part number	Varies by part number
Main Purchasing Consideration	Prescribed feeding setup and compatible ports	Prescribed feeding setup and connector configuration

Important: The terms continuous and bolus describe product configurations and intended applications. They do not mean every set in either category is interchangeable. Follow the prescribing clinician's directions and the manufacturer's instructions.

What Is an ENFit Feeding Tube Connector?

ENFit is an enteral-specific connector design developed to reduce the risk of connecting feeding equipment to incompatible medical delivery systems.

ENFit connectors are based on the ISO 80369-3 standard for enteral applications.

The goal is to help distinguish enteral feeding connections from connectors used for other medical purposes, such as intravenous administration.

For customers ordering feeding tube supplies, this means the connector configuration is an important product specification.

ENFit vs. Legacy Feeding Tube Connectors

Feature	ENFit Connector	Legacy Enteral Connector
Design	Enteral-specific standardized connection	Older connection designs
Standard	Based on ISO 80369-3	Varies by product
Compatibility	Requires matching compatible enteral components	Requires matching legacy components
Common Application	Modern enteral feeding systems	Existing or older feeding systems
Ordering Requirement	Confirm ENFit compatibility	Confirm exact legacy connector type

An ENFit connector on the feeding equipment end does not necessarily change the SECUR-LOK connector used at the MIC-KEY button.

These are different connection points, and both must be compatible.

Can I Use an ENFit Extension Set with an Older MIC-KEY Button?

Compatibility depends on the specific button and extension set.

Some MIC-KEY extension sets use the familiar SECUR-LOK connection at the button while incorporating an ENFit connector at the opposite end.

However, this does not mean every extension set is compatible with every feeding tube or feeding administration system.

Verify the exact product models and manufacturer compatibility information before purchasing.

Never force incompatible connectors together.

What Is the SECUR-LOK Connector?

SECUR-LOK is an Avanos connection mechanism used on MIC-KEY feeding tube extension sets.

It is designed to connect compatible extension sets to the appropriate low-profile feeding tube access port.

Avanos offers SECUR-LOK extension sets in both right-angle and straight configurations.

Right-Angle vs. Straight MIC-KEY Connectors

Right-angle extension sets have a connector that directs the tubing outward at approximately 90 degrees from the button.

Straight extension sets have a more direct connector orientation.

The appropriate configuration depends on the exact device, prescribed feeding arrangement, and manufacturer instructions.

Neither connection style should be substituted solely based on appearance.

MIC-KEY Extension Set Lengths: 2, 12, and 24 Inches

Avanos lists MIC-KEY extension set configurations in several lengths, including:

• 2 inches: Short extension configurations

• 12 inches: Common extension length

• 24 inches: Longer extension configuration

Not every extension set style is available in every length.

The correct tubing length depends on the prescribed feeding arrangement and the specific compatible product.

Longer tubing is not automatically preferable, and a shorter set is not necessarily appropriate for every setup.

Avanos MIC-KEY Extension Set Part Number Comparison

One of the best ways to identify the correct replacement accessory is by using the exact Avanos manufacturer part number.

The following examples illustrate common MIC-KEY extension set configurations listed in the manufacturer's product catalog.

MIC-KEY Extension Set Reference Chart

Avanos Part Number	Extension Set Type	Connector Configuration	Length	ENFit
0121-12	Continuous	Right-angle SECUR-LOK, two-port Y	12 in	No
0121-24	Continuous	Right-angle SECUR-LOK, two-port Y	Manufacturer listing requires confirmation	No
0123-12	Bolus	Straight SECUR-LOK, catheter-tip/bolus	12 in	No
0124-24	Bolus	Right-angle SECUR-LOK, catheter-tip/bolus	24 in	No
0141-12	Continuous	Right-angle SECUR-LOK, two-port Y	12 in	Yes
0141-24	Continuous	Right-angle SECUR-LOK, two-port Y	24 in	Yes
0143-12	Bolus	Straight SECUR-LOK	12 in	Yes
0144-12	Bolus	Right-angle SECUR-LOK	12 in	Yes
0144-24	Bolus	Right-angle SECUR-LOK	24 in	Yes

Source: Avanos MIC-KEY Feeding Tube Extension Sets product catalog. Some legacy listings contain inconsistent length information; verify the individual product's current technical specifications before ordering.

What Is the Difference Between Avanos 0121 and 0141 Extension Sets?

The 0121 series includes legacy, non-ENFit continuous feeding extension sets.

The 0141 series includes ENFit continuous feeding extension sets.

Both families include right-angle SECUR-LOK configurations, but their feeding-system connector specifications differ.

For example:

• 0121-12: Continuous feeding extension set, 12 inches, non-ENFit

• 0141-12: Continuous feeding extension set, 12 inches, ENFit

They should not be considered automatic substitutes without checking the entire feeding system.

What Is the Difference Between Avanos 0123 and 0143?

These product families include straight SECUR-LOK bolus extension set configurations.

The 0123 series contains legacy, non-ENFit configurations, while the 0143 series contains ENFit configurations.

Exact connector descriptions and packaging vary by individual SKU.

What Is the Difference Between Avanos 0124 and 0144?

Both product families include right-angle SECUR-LOK bolus extension sets.

The 0124 series includes legacy catheter-tip/bolus connections.

The 0144 series includes ENFit bolus connector configurations.

For example:

• 0124-24: 24-inch right-angle bolus extension set, non-ENFit

• 0144-24: 24-inch right-angle bolus extension set, ENFit

Check the manufacturer's part number rather than assuming that products with similar names are interchangeable.

Are MIC-KEY Extension Sets Universal?

No. MIC-KEY extension sets should not be considered universal feeding tube accessories.

Compatibility depends on the manufacturer, button model, connection mechanism, connector type, and approved intended use.

A product designed for a MIC-KEY button may not fit a different manufacturer's low-profile feeding button.

Similarly, a compatible connection at the button does not guarantee that the other end will connect to the patient's feeding bag, syringe, or pump administration set.

Before purchasing, confirm compatibility at both ends.

Do MIC-KEY Extension Sets Come in Different French Sizes?

MIC-KEY G-tube buttons are commonly identified by French size and stoma length.

Extension sets, however, are generally selected according to their compatible device family, connector configuration, and tubing length rather than by matching the button's French size.

For example, a patient with an 18 Fr MIC-KEY button may require a specific SECUR-LOK extension set identified by its own manufacturer part number.

The French size alone is not enough to determine the correct accessory.

Always verify the exact feeding tube and extension set combination.

How Often Should a MIC-KEY Extension Set Be Replaced?

Extension set replacement depends on the manufacturer's current instructions, the specific product, and the patient's care plan.

Do not assume that the extension set should be replaced on the same schedule as the feeding tube button itself.

Extension sets may require replacement due to their labeled use period, damage, connector wear, or other conditions identified by the healthcare team.

For cleaning, reuse, and replacement instructions, follow the exact product's instructions for use.

How to Order the Correct MIC-KEY Extension Set

Before purchasing a replacement extension set, gather the following information.

MIC-KEY Extension Set Ordering Checklist

1. Identify the feeding tube manufacturer and model. Confirm that the device is a compatible Avanos MIC-KEY product.

2. Confirm the extension set type. Continuous, bolus, or another prescribed configuration.

3. Check the button connector. Identify the required SECUR-LOK configuration.

4. Verify ENFit compatibility. Confirm whether the feeding administration equipment requires ENFit or another specified connector.

5. Confirm the tubing length. For example, 12 or 24 inches.

6. Identify the manufacturer part number. Use the exact SKU whenever possible.

7. Check the quantity and packaging. Some products are sold individually or in manufacturer cases, depending on the SKU.

8. Confirm prescription and supply requirements. Verify any required documentation before ordering.

Using the manufacturer's part number is especially helpful when purchasing multiple extension sets for a facility or managing recurring supply orders.

Frequently Asked Questions About MIC-KEY Extension Sets

What is a MIC-KEY extension set used for?

A MIC-KEY extension set connects a compatible low-profile feeding tube button to enteral feeding equipment for prescribed feeding, hydration, or medication administration.

What is the difference between continuous and bolus MIC-KEY extension sets?

Continuous extension sets commonly have right-angle connectors and Y-port configurations, while bolus extension sets commonly use single-port straight or right-angle configurations. Exact designs depend on the SKU.

Are all MIC-KEY extension sets ENFit?

No. Avanos offers both ENFit and legacy non-ENFit extension set configurations.

Is Avanos 0121-12 the same as 0141-12?

No. Both are 12-inch continuous feeding extension sets with right-angle SECUR-LOK connectors, but 0121-12 is listed as non-ENFit and 0141-12 as ENFit.

What is Avanos 0121-24 used for?

It is a legacy MIC-KEY continuous feeding extension set with a right-angle SECUR-LOK connector and two-port Y-configuration. Confirm the current manufacturer specifications, particularly tubing length, before ordering.

What is Avanos 0144-24?

It is a 24-inch MIC-KEY bolus extension set with an ENFit connector and right-angle SECUR-LOK connection.

Can I use a MIC-KEY extension set with another brand of feeding button?

Do not assume compatibility. Use the manufacturer's approved accessory information for the exact feeding tube model.

Does the extension set need to match the G-tube French size?

Not necessarily. Extension sets are selected based on device and connector compatibility rather than French size alone.

Can I use a bolus extension set for continuous feeding?

Only when permitted by the manufacturer's instructions and the patient's prescribed feeding setup. Do not assume that different extension set configurations are interchangeable.

Where can I buy MIC-KEY extension sets?

Medical supply distributors, including Lexicon Medical Supply, can assist with product inquiries for Avanos MIC-KEY extension sets and related enteral feeding supplies.

Shop Avanos MIC-KEY Extension Sets at Lexicon Medical Supply

Looking for a replacement MIC-KEY extension set, ENFit connector, or enteral feeding accessory?

Lexicon Medical Supply helps healthcare providers, facilities, caregivers, and purchasing departments identify and source medical supplies.

Whether you need a MIC-KEY continuous feeding extension set, bolus extension set, or ENFit-compatible accessory, our team can assist with product inquiries and availability requests.

For faster assistance, provide the Avanos manufacturer part number, desired tubing length, connector configuration, and required quantity.

Visit Lexicon Medical Supply to explore available enteral feeding supplies or contact our team for purchasing assistance.

Related Reading

For more information about MIC-KEY feeding tubes, explore our companion guides:

• Avanos MIC-KEY Feeding Tubes: G-Tube Buttons, Sizes, Extension Sets & Buying Guide

• MIC-KEY Button Sizes Explained: French Sizes, Stoma Lengths & Avanos Part Numbers

*Medical disclaimer: This article provides general product education and purchasing information. It is not a substitute for medical advice. Feeding tube accessories must be selected a