12mm John Guest Tube Insert

The 12mm John Guest Tube Insert is designed to reinforce plastic tubing and ensure a secure, long-lasting push-fit connection. Installed directly inside 12mm tubing, this insert provides structural support and helps prevent tube distortion under pressure.

Ideal for use in caravan, marine, and low-pressure water systems, the tube insert is essential when connecting softer or flexible tubing to John Guest fittings. It promotes a better seal and extends the service life of your connection.

Key Applications

• Caravan and RV plumbing

• Marine fresh water systems

• Filtration units and beverage lines

• Irrigation systems using polyethylene tubing

Product Features

• Suits 12mm plastic tubing

• Strengthens tube ends for leak-free sealing

• Compatible with all 12mm John Guest push-fit fittings

• Easy to install—simply insert before connecting

• Made from high-strength acetal plastic

Why Choose John Guest Fittings?

John Guest fittings are a preferred solution for professional-grade plumbing and fluid systems. This 12mm tube insert ensures your fittings perform at their best by supporting tubing under pressure or frequent use.