Advantage 4 1/2 x 7/8 Zirconia Flap Wheels 80 Grit 10 Pack Grinding Wheels The 155 has a medium

The 155 has a medium to heavy preheat & six preheat acetylene holes

The tips are sized by the oxygen hole bore size which is in incerse order of the numbers

Max RPM 8700

these heating heads deliver consistent

045 for Max 40

Advantage 4 1/2 x 7/8 Zirconia Flap Wheels 80 Grit 10 Pack Grinding Wheels The 155 has a mediumOur Advantage Zirconia Flap Discs are 4 1 2 inch diameter for small angle grinders. They 1 2 inch thick with resin coated paper backing. The 7 8 inch arbor hole has a durable metal outer layer. The 7 8 inch arbor is standard on 4 1 2 inch angle grinders but does require a retaining nut that comes with the grinder. These zirconia flap discs for sale are ISO 9001 certified. They have a maximum RPM of 13,300 . The 80 grit zirconia is considered a fine