Camel Grinding Wheels' trimmable Z3 flap discs have a disc backing designed for the user to trim down to expose flaps for extended working life, allowing for fewer disc changes and longer production times. The trimmable discs have a hybrid compact flap design that compresses and compacts flaps at a 4-degree angle for additional edge strength and 20-percent more material than regular Z3 flap discs. Available in 4 1/2" and 5" diameters, with 7/8" arbor holes and 40-, 60- and 80-grit sizes.