Which Press Jaw?

How do I find the right press jaw for the fitting

Whether you are installing heating pipes, water pipes, or underfloor heating – fittings are usually essential. To create a tight and secure connection between pipe and fitting, you will in most cases need a pressing machine, such as the ROTHENBERGER ROMAX AC Eco or the REMS Power Press SE, together with the appropriate press jaw (also called press tongs) matching the fitting and pipe material, and featuring the correct contour. While we cover the selection of the right pressing machine in a separate article, this guide focuses on selecting the correct press jaw and contour. Whether M18, V15, or TH26 – the variety of contour types is large, and the confusion often even greater when it comes to choosing the right press jaw for your existing or new pressing machine and the required fitting. To help you confidently choose the right press jaw and contour for your next project, we’ll take you on a short journey into the world of fittings and press jaws.

Important note: Please refer to the manufacturer lists from ROTHENBERGER and REMS linked below as an additional selection guide, as this article can only provide an initial introduction to the topic.

Why must the press jaw match the fitting?

Choosing the correct press jaw for the fitting and pipe material is crucial for successful work results. Why? Because every fitting requires its own pressing contour (also called press profile), and this contour is created during the pressing process by the press jaw. Therefore, the contour of the press jaw must match the fittings being used so the integrated sealing elements are correctly pressed onto the pipe, ensuring a leak‑free connection. Some fitting systems are designed so that multiple contours are compatible. For example, the FRÄNKISCHE alpex F50 PROFI system can be pressed with the contours F, H, TH, U, or VP.

M18, V15, TH26 – Where do these abbreviations come from?

Anyone who has ever looked at the labels on press jaws has surely noticed the combination of letters and numbers. At first glance, they may seem random, but they actually provide important information. The letter generally indicates the original fitting manufacturer who developed or introduced the contour, and sometimes also refers to the entire pressing system. The numbers following the letters indicate the pipe diameter that the jaw presses. For example, “SV35” stands for the manufacturers Seppelfricke/Viega and a pipe diameter of 35 mm. “VRX20” refers to the Viega Raxofix system with a pipe diameter of 20 mm. Since not every fitting manufacturer develops its own contour, some contours are compatible with pressing systems from other manufacturers. A good example is the TH16, which is also compatible with the Sanpro THPRESS 16 mm pressing system.

Does every press jaw press every material? No!

The question of whether one press jaw can press composite, stainless steel, copper, and C‑steel pipes must clearly be answered with “No”. But which press jaw presses which pipe? The pressing contour does not only depend on the pipe material — it must match the entire fitting/pipe system.

Why “SC‑Contur” is not a press jaw contour

Even though the name suggests it, the term “SC‑Contur” does not refer to a fitting contour or a specific pressing system. It is used by the manufacturer Viega for fittings designed to be “leak‑detectable when unpressed”. This means that during pressure testing, leaks become immediately visible if a fitting has not been (properly) pressed — as water or air escapes from the unpressed area — preventing potential water damage.

Today, other manufacturers also offer unpressed‑leak fittings, but they may not use the trademarked term “SC‑Contur”. Examples include the Sanpro THPRESS composite pipe system or the Sanpro V Profile Copper Press Fittings, which also feature unpressed‑leak detection and thus provide enhanced safety against water damage.

A selection guide – lists of suitable press jaws / press tongs:

The manufacturer lists from ROTHENBERGER and REMS linked below provide an overview of all contours by system provider (fitting/pipe system manufacturer) and help you choose the correct contour for your project. If you cannot find your fitting system in the lists, please contact the manufacturer or your fitting supplier for information on the required contour. Manufacturers usually offer this information on their websites.

REMS – Press jaw/press tong contours

ROTHENBERGER – Press jaw/press tong contours

Also helpful is the “Pressnavigator” app by ROTHENBERGER, which supports users in selecting the right pressing tools and fitting systems. The app is available for Android and iOS.

In summary, there is no universal pressing contour that can be used for all pipe and fitting combinations. Instead, the correct press jaw must be selected individually before beginning the work. The rule is simple: To avoid costly water damage, every pressing system must be pressed with the contour chosen and tested during its development.

An overview of the 9 most common pressing contours

To give you a better understanding, we have compiled the 9 most commonly used pressing contours in Germany, together with an example fitting. Click on the image to go directly to the corresponding product in our online shop.

Please note that all example combinations shown are standard press jaws for 32 kN machines, which fit almost all pressing machines from most manufacturers. If you are using a “Mini” (22 kN), “Kompakt” (24 kN) or “Compact” (19 kN) pressing machine, you will need jaws from the respective manufacturer. You can find them via our shop search or category navigation. If you have questions, we are happy to help.