Ka lebaka la khetho ea thepa ea ho tiisa ke EPDM kapa NBR. Belofo e bonolo ea heke e ka sebelisoa ka mocheso o phahameng oa 80 ° C. Hangata e sebelisoa liphaepheng tsa ho hloekisa metsi bakeng sa metsi le litšila tsa metsi. Li-valve tsa heke tse koalang tse bonolo li fumaneha ka maemo a fapaneng a moralo, joalo ka British Standard, German Standard, American Standard.Khatello ea lebitso la valve e bonolo ea heke ke PN10,PN16 kapa Class150.