Politubes semicaps are designed with a radius closure, allowing easy insertion of seals into mechanical components with sharp edges, while preventing potential damage.

Thanks to their versatility, they can be used in multiple applications, such as:

• mounting and protection of seals and gaskets;
• installation in engine heads and valve guides;
• serving as technical spacers in various mechanical parts.

A common application is the protection of O-RINGS in internal combustion engine valves: the semicaps facilitate insertion, prevent seal damage, and—thanks to the radius closure—also prevent the cap from slipping on the valve.

Additionally, this product is widely used during the assembly of Dunlop, Schrader, and Presta valves in tires, avoiding direct contact between the valve metal and the tire, which could otherwise cause damage.