33F, 37F, 40F series character: Punch forming 304 stainless steel casing, copper thread connection.

33FS, 37FS, 40FS series Character: Punch forming 304 stainless steel casing, 304 stainless steel thread

 connection, and 304 stainless steel bourdon tube. The excellent corrosion resistance of 304 stainless

steel make it can be used for all kinds of extinguishing agent.

33FL, 37FL, 40FL series character: Aluminum alloy casing, surface treated to avoid chemical reaction with

copper valves. Punching aluminum alloy case, ecnomic price.

33FL, 37FL, 40FL series has same appearance with 33F, 37F, 40F series. Their common character:

304 stainless steel bourdon tube, big indicating angle of the

pointer due to the high elasticity of the material. Work at temperature from -30℃ to 60℃

The material does not fatigue after subject to 1000 pressure cycle

test. Laser welding of the bourdon tube ensures excellent leakage resistance, and will not

leak under a pressure 6 times of the working pressure. The window

is made from unbreakable PC plastic. The indication is accurate and distinct for reading.