Features: guide rail, smooth experience. Flexible/Rustproof. The widest support is 53mm, and the screw with the thickest support is 20mm (thick chisels can replace long screws for fastening, and the screws M6). the guide rail is smooth and flexible, and the grindings angle can be adjusted freely to adapt to different styles of chisels. The clamping capacity is 53mm, and the grindings angle can be adjusted freely to adapt to different chisels. The grindings stone adopts a double-sided design, with a rough surfaces of 1000# that can be ground and a fine surfaces of 6000 # that can be polished and sharpened. Specifications: Material: Aluminum alloy Package Includes: 1PC x Sharpening Holders note: Please allow 0-1cm error due to manual measurement. make sure you not mind before you bid. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you!