An abrasive flap disc can help you grind and finish metal surfaces with one tool attachment. Flap discs grind like a depressed center wheel and finish like a fiber sanding disc – helping you reduce process time and lower your total grinding costs.

Technically speaking, Type 27 Flat flap discs have a flat flap design and provide the best finish. These tend to be the most popular and commonly used. Type 27 Flap Discs are used primarily on flat surfaces they grind at flatter angles 0° to 15°.
 
Type 29 Conical flap discs are the more aggressive choice, with flaps angled at 10°. The angle provides greater surface contact. A Type 29 flap disc can be used on both irregular and flat surfaces and grinds at steep angles 15° to 25°.
 
Choose a Type 29 angled flap disc for faster stock removal. An angled edge can be used with a vertical or horizontal
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