BL Startrails Aluminium Grinder 4-partThe 'Startrails' Grinder from Black Leaf is made of abrasion free, anodised aluminium. It comes without screw thread. Screen and bottom chamber can be opened without much effort with a turn thanks to the bayonet joints. The lid is held by a strong magnet. 20 strong and sharp rotor blades shred your herbs in next to no time. The herb mill has a pollen screen which is attached with the only screw of the grinder. This makes it easy to remove the screen