... the engine room , thus play a role in sealing, apply to mobile base station,exchange,microwave station etc. kinds of engine ... one hole sealing elementM1630117/8” two hole sealing elementM1630137/8” three hole sealing elementM1630141/2”4 hole sealing elementStainless ateel HLKCModel ... two hole sealing ring,with borderH1030122mm, 9 hole,7/8 three hole sealing ring, with border(NBR)H1030152mm,12 hole, ...