Toolzone 36 grit zirconium sanding flap disc wheels for use with 4 12 115mm angle grinders and sanders ideal for removing rust grinding of welds parting lines on casting and carbon steels or removing rough edges on most surfaces zirconiums excellent resistance to corrosion aids in the process of sanding for a longer and more durable use lasts up to 25 times longer than a regular sanding disc pack of 10 size 115mm x 22mm colour blue