Norton 66623399002 Flap Disc 80 Grit 4.5 in Type 27

Product Description

The NORTON 66623399002 is a Type 27 coated flap disc designed for aggressive material removal and surface blending on metal. It uses ceramic alumina abrasive, a self-sharpening grain that maintains cut rate longer than standard aluminum oxide under high-pressure grinding. The disc measures 4.5 inches in diameter with a 5/8-11 arbor hole and carries an 80 grit medium grade rating. A polyester backing supports the flap stack, providing flexibility during contouring work. Maximum operating speed is 13,300 RPM. This disc is suited for use on angle grinders operated by welders, fabricators, and metalworking tradespeople performing weld blending, deburring, and surface prep.

This flap disc is used primarily in metal fabrication shops, welding operations, and structural steel work where consistent stock removal and a smooth finish are required in a single pass. The Type 27 flat-profile design works well on flat and slightly contoured surfaces. The trimmable construction allows the operator to expose fresh abrasive as the disc wears, extending usable life. The green disc color identifies the ceramic alumina grain series within the NORTON product line.

Key Features

• Ceramic alumina abrasive grain for extended cut life and consistent performance under pressure
• Type 27 flat profile suited for flat surface grinding and weld blending
• 80 grit medium grade balances stock removal with surface finish quality
• Polyester backing provides flexibility for light contouring applications
• Trimmable flap construction extends disc service life
• 5/8-11 arbor attachment fits standard angle grinder spindles

Compatibility

Designed for use on angle grinders with a 5/8-11 spindle thread accepting 4.5 inch Type 27 flap discs rated at or below 13,300 RPM.

Installation Notes

Installation and use should be performed by qualified personnel familiar with abrasive wheel safety per ANSI B7.1 guidelines. Always confirm the grinder's rated RPM does not exceed the disc maximum of 13,300 RPM before mounting. Power down and disconnect the tool from its power source before mounting or removing the disc. Never exceed the maximum RPM rating and always use the appropriate guard for Type 27 disc operation.