The 3514 and 3515 controls are small, compact mechanical control heads with valves incorporated to allow for station transfer on multi-station pneumatic systems. The 3514 / 3515 has a handle to actuate and switch the flow and transfer control to a different station.
The 3514 / 3515 valves are constructed entirely of bronze & stainless steel, and are available in 1/8" NPT and a 1/4" NPT respectively. The photo shown is of a 3514.