Two hand slam is the act of pleasuring ones self with both hands vigorously. Commonly done by males with an average penis size to make them think it's bigger than it actually is. If one is fortunate enough to receive said two hand slam it will be a very memorable experience and cause you to only pleasure yourself with it from here on out
Guy 1: Man, both of my forearms are super sore
Guy 2: Bro, it's gotta be from all the jerking off
Guy 1: No its not that...
Guy 2: Once you get used to the two hand slam your forearms won't hurt anymore. Trust me
HOOKER: "Okay you got two blowjobs and half a handjob, that will be $4.50"
DUDE: "What? That's a bit steep, I thought you told me a handjob was only a dollar!"
HOOKER: "Its fair. A dick in the mouth is worth two in the hand"