Identification help - metal key ?

Hello everyone. I need help in identifying this object. It appears to be some kind of key. It is 8 1/2” long. Weighs about 16 oz. Made from some type of metal. Has hallmarks on it. Any type of help would be greatly appreciated.

 

Key is possible but if so the handle end is very poor human-factors-Wise. When you photograph dark objects for surface details, use a neutral background other than white as white causes a very short “exposure” hiding dark details. I routinely use a flattened brown cardboard box as photo background. Thing might just be part of an unknown machine.

 

Machines with gear cases, like tractors and such, often have flush 'pipe' plugs in threaded holes to check or drain lubricants. These plugs come in various sizes, and require a correctly sized wrench to turn them. (Some, but not all, came in standard 3/8, 1/2 or 3/4-inch sizes so you could just use a ratchet extension to turn them.)

There are 'fit-all' wrenches with the various sizes. Some of your lugs show torque damage.

Are the lugs different sizes?

 

Here's what I'm thinking of:

https://www.ebay.com/itm/VINTAGE-KE...CH-OLD-TOOL-/401086400479?hash=item5d629cc7df

 

Thank you all for your help.

 

Yes that’s what I believe that it is as well. Multi size drain plug wrench.