Diamond hand profilers/router bit F30 (30mm, 1 1/4”) fits on any variable speed or fixed speed grinders or polishers with 5/8"-11 thread spindle. They are designed for 30mm(1 1/4") thick ogee edge profiling on slabs of granite, marble, concrete, natural stones, engineered stones and concrete countertops. Adopting the latest "Vacuum Brazed Technology", our profilers give you aggressive grinding action and longevity, without losing the shape of the profile, unlike the Sintered profilers on the market. The nylon guide on the top of the bits slides along the surfaces steadily and the rotary touch bearing controls the depth smoothly. They have internal water feed for cooling. Optimal speed is 3,500-4,000RPM. Wet or dry use.