4.5", 40 Grit, jumbo blue Zirconia, type 29, flap Disc, 5/8 11" arbor, high density Depressed center, for right angle grinders, cuts fast & outlasts sanding discs 10 to 1, great flexibility, ideal for rough or fine finishing, high density discs are ideal for the extra tough jobs, long lasting, cooler running jumbo style.