Flap discs are versatile grinding and finishing tools with three main components - backing plate, adhesive, and abrasive flaps. The flaps wear during use continually exposing new abrasive grain. The different variations of the components provide a variety of applications, ranging from heavy stock removal to blending to finishing. Flap discs are designed for portable grinder applications and can combine the 2-step stock removal and finishing operations of depressed center wheels and fiber discs into one operation.