AOP Precast produced CE certificated Ring Clutch (lifting clutch) with high grade 35CrMoV special casting head clutch and forged bolt. When the head of ring clutch inserted into the recess and anchor head, the bolt will lock down the anchor from head of ring clutch. The ring clutch casting head need to special head treatment to improve mechanical behavior. The forged bolt need the same materials with head. The lifting clutch hook was made by enough thickness and high strength steel. The ring clutch hook welded need high quality and deeply to approval with X-ray machinery.