Combination of cocaine powder and MDMA crystals. Generally a point of MDMA mixed with a half gram of cocaine; can vary though. Slap is snorted in bumps or lines. It is called "Slap" because of the intense rush within seconds of use.
"Hey, let's do some Slap."
*lays out line*
"Woooooooo, that's why they call it Slap."