1.2.5"(63mm), back glycerine filled manometer 2.S.S case,Brass connection,S.S ... bezel, 3.0-4bar,1/4NPT etc. 63mm(2.5") Glycerine filled manometer ,bayonet bezel ,YN63ZB BRIEF INTRODUCTION Oill filled pressure ... /4", 3/8",1/2", PT,BSP,NPT etc. Fill: Glycerine(standard) Silicone(optional) Gaskets/Filling cap: Neoprene Or Silica gelOPTION ...