Three-position, four-way manual air valve

1. Selected materials: cast in aluminum alloy, the cylinder is firm.
2. Small size: real material, light weight, easy to disassemble.
3. Long-lasting operation: precision casting, guarantee sealing and longer service life   
Product name:Three four-way hand-turn valves.
Size :90 high MM,74 MM wide
The difference between hv-02 03 04 and hv-02 03 04 is that the interface size is different,
Interface thread diameter.12mm,
03Thread diameter of interface16MM,
04Interface thread diameter20MM.
P hole main intake, a hole B reversing control cylinder front and rear cover, R hole exhaust (with muffler)

Technical description:
1. Why does the new valve leak from the vent when installed?
Answer: this is cylinder string gas: the piston seal ring in the cylinder leaks, the gas runs directly from one end of the cylinder to the other end from the valve exhaust hole, is mistaken for the valve quality problem.