Samson 504351 "504 series" high pressure hose reel.
Auto rewind.
Comes with 50' x 3/8" high pressure (5,000 psi) hose and 3/8 NPT whip.
I briefly used this with a power washer at my home, but it's just too heavy-duty for this use. I think this is intended for grease. It's only ever been used with clean water, so is in excellent condition with very few signs of use.