The piston seal type Aston Seals YAB is composed of a dynamic seal element which assures exceptional low friction and high speed performance, high compatibility with nearly all media due to the chemical resistance which exceeds that of all other thermoplastics and elastomers. - A standard size O-Ring with low permanent deformation as energizing component on the static side • Low static and dynamic friction • High speed allowed • No tendency of stick-slip • Space-saving construction and simple groove.