Lyman's bleacher loading blocks features a stepped design which allows you to easily grip a single case without jamming your fingers.It is made of tough, durable polymer and is molded in three sizes to closely fit a variety of rifle cases.This model is model to 223 remington caliber with a.388 diameter.Capacity: 50 CasesType: Loading BlockCaliber: 223 RemSize: .388Quantity: 1Function: Holds CasesCompatible With: 223 Caliber CasesMaterial: PolymerFinish: Orange