This sale is for one import swivel base for 6" Milling Machine Vises. It is made of cast iron. It has a center pivot pin that measures 30MM in diameter as seen in one of the photos. (the digital caliper and scales are not included with this sale). It has a small factory-made cosmetic defect shown in the pictures that does not affect the performance of the base. This sale is for the base only with NO clamping bolts or anything else included. The measuring calipers and scales seen in the photos are NOT included in this sale.