I have alot of Proto torque wrenches including this one and the all metal Protos are great and if you want to send it somewhere for calibration Angle Repair in Beckley WV is very good and reasonable.
Just saw this old thread and you got a heckuva deal. This Proto is a beast; built much heavier than the equivalent Snap-on/Precision Instrument.
One nice feature is it's not necessary to crank the handgrip for an hour to get to the top of the scale or off to the bottom. It adjust full range with just a few turns.