Tightlok grooved bolt is made of hot rolled bar with several forged grooves at one End, usually used for hardrock support. Features: (1) Groove device makes resin mixing easily and completely. (2) Fast and easy installation by mechanized tools. (3) Used together with resin cartridge for permanent support. (4) With pin nut device, nut can help drive the rod to mix the resin. It is based on the request of each client.