Coil Voltage: 12 V-DC Port Size: 1/8 IN Frequency range 10-20Hz.(20Hz will allow a wider duty cycle tuning range than 30 Hz for this valve) Bracket facilitates robust and easier mounting. User must supply an M6 flat head screw to mount the bracket to their intended object, as each installation requires a unique length. ACE hardware carries these in various lengths. Note: The valve will be marked/identified in some way to endure that it was sourced from Circuit Se7en and is a genuine MAC valve.