Im guessing you know what a bong is being you know what its called so id say its probably an oil rig to smoke oil, dabs, BHO, wax, honey comb and such just a guess
You can use a bong for whatever. Generally though, if it has a female connection(like yours), its made for using weed bowls. If it has a male connection(smaller) its made for nails. They make all kinds of adapters for the bong downstem. Btw that is a nasty ass ash tray lol
Good lord, it's a BONG.....you seem to have that already!
Now for some information you should know!
When taking pictures of bongs, weed, buds, etc, etc. The background should be uncluttered and NOT contain the bodies of shirtless MEN! Topless FEMALES ONLY!
Now after I wash my eye's out I can continue my "trip" through RIU......Kids these days....Fah!