D-lead soap...
Bought a bottle myself, am using it for cleanup after handling bullets, reloading, shooting, etc. I find it to be a VERY good surfactant. (That is, it gets very "soapy" with the water; floats stuff off the hands well.)
Previously had been using Dawn dishwashing detergent for the same purposes, and that is also a very good surfactant. The difference between Dawn and D-Lead is so small as to not be discernible.
Another option is Dr Bronner's 18-in-1 Peppermint Pure Castile Soap, a specialty soap sold locally but made out in CA. The label is covered with hype; takes a while to read. However, it, too, is a very good surfactant, IMX. Bought it originally to take camping. Supposed to be good for hands, dishes, dogs, everything.
The D-Lead does not require very much at all to do a good job. Nor does Dr. Bronner's, for that matter. Have not made a price comparison between these 2 and the Dawn.
FWIW, Dr. Bronner's smells the nicest of the 3.