This is a nicely made, all steel, grease gun or pusher as it is sometimes called, for injecting small amounts of grease into mechanics of tools and machines. It is clearly marked "K - D NO. 416 MADE IN USA US PAT. 2,955,627". It is 4.9" long overall with the pusher stem fully inserted. The injection hole diameter is .156" with a chamfer. The internal injection stem is in great shape with what appears to be chrome plating on it. The internal injection stem is .35" diameter and has about 1.6" of travel in and out. A handy mechanic's tool for your shop!