The Cross computer stock number is stamped in the shaded area on the handle end of the valve body on recent valves.
VS2, AD, SQV, & DCV stamped With last 4 digits on machined Surfaces or plugs
On older valves, the Z casting number is on the back which would tell you which series, but individual functions would have to be described. (ex. IZ0046, 1Z0202 etc.)
BA, BC, CA, CD & SS
SD & VS4 without solenoid
Solenoid or Pilot end caps