The K Valve is the old style and has 1 mounting bolt hole, whereas the new style K Valve has 2.
Kingston Quick Opening Flow Control Valve features a forged brass body, a brass stem and stainless steel spring. The valve stem is electroless nickel plated for long wear in harsh solutions. Buna-N disc and O-Ring provide a positive seal. Lever Option - A, 5" Steel Lever
The Kingston Series Flow Control Valves were all developed for use in car wash, carpet cleaning and other systems that require a durable control valve using mechanical contact to operate the valve.