"This 12-pc. 3/8in. drive metric universal standard impact socket set is made with chromium molybdenum alloy steel for strength and features a 12-point design for less fastener wear. Measurement Type Metric, Metric Socket Size mm 7-19, Point 12, Material Type Chrome molybdenum, Pieces qty. 13, Drive in. 3/8, Storage Type Plastic case, Specialized Pieces qty. 0. Universal joint helps reduce wear by working at off-angles"