It appears to be a snapon clicker, probably 3/4" drive for they are useing it for I have a 1/2" drive good to 200lbs,and 2 inch lb clickers, gotta have them for setting up rearends and i don't think you want a few unless you have deep pockets. Sears makes one for about 1/2 the price as snapon. I really thought every one uses the clicker, as stated above set it to what you want your torque and it will click when you reach the ft.lbs. it's set for. But after use be sure to back it off to "0" or no load on the spring.
In plastic box, all are crome.
Zip.