Reddit mentions of NR00910EA - No-Rinse Body Bath 16 oz.

Another low-cost option for hygiene is Rinse-Free body wash. When I lived for about 2 1/2 years in a conversion van with no plumbing or electricity, this kept me clean enough to teach a college class without anyone ever saying anything to me. I purchased an 8 ounce bottle of ready-to-use rinse-free shampoo and used it for shampoo and body wash. When that was depleted, I got a 16 ounce bottle of body wash concentrate. One capful of concentrate in the 8 ounce bottle and fill with water. Dampen a washcloth and scrub yourself. Either dry the washcloth with the air dryer in the restroom or put it in a Ziplock until you can air dry it elsewhere. One 8 ounce bottle could last up to a week, and a 16 ounce bottle of concentrate made 64 bottles of diluted solution. Total cost was under $20 ($6 for the 8 ounce bottle, $8 for the 16 ounce bottle, $5 for a package of washcloths) and that would provide about a year's worth of hygiene. Even now I still use Rinse-Free when I'm pressed for time and can't take a proper shower.