The Bosch DBX4541E is a 4 1/2" X-LOCK Xtreme Segmented Rim Diamond Blade. Quality diamonds deliver fast cutting and longer life. This blade features an X-LOCK wheel change, which has snap-on mounting and a wheel-release lever on grinder for a change-out up to five times faster. It has a segmented rim diamond blade designed for fast universal rough cuts in concrete, brick, masonry. It is a genuine Bosch product.