1. Zirconia flap disc, with fiberglass backing pad
Size Arbor GRIT MAX RPM Type
4" 5/8" 36# 40# 60# 80# 120# 15300 T27 & T29
4-1/2" 7/8" 13300 T27 & T29
5" 7/8" 12000 T27 & T29
7" 7/8" 8600 T27 & T29

2. Aluminum Oxide flap disc, with fiberglass backing pad
Size Arbor GRIT MAX RPM Type
4" 5/8" 36# 40# 60# 80# 100#120# 15300 T27 & T29
4-1/2" 7/8" 13300 T27 & T29
5" 7/8" 12000 T27 & T29
7" 7/8" 8600 T27 & T29

T-27/Flat - Used when grinding on flat surface, correct angle recommended between 0-15 degrees, best choice for smooth finishing.

T-29/Conical - Built in angle for grinding, this design is excellent for contour and edge work, angle at 10 degrees. It also provides greater surface contact and is more aggressive. Best at more dramatic angle of 15-25 degrees.