Chromium-plated caps fitted to some wheel nuts are prone to swelling, making them incompatible with standard whole-size sockets.Half sizes allow the secure fitment for safe removal.Chrome molybdenum socket is hard-wearing, tempered and anodised for corrosion resistance.Durable thin-walled design for use with impact tools.Double-ended 6-point socket is externally sleeved to prevent damage to alloy wheels and nuts.Socket sizes: 18.5 x 19.5, 19 x 21, 21 x 21.5, 22 x 22.5mm with a 75mm 1/2"Sq Drive Extension.Model No. SX1820SCHROMIUM-PLATED CAPS FITTED TO SOME WHEEL NUTS – These are prone to swelling, making them incompatible with standard whole-size sockets.HALF SIZES - Allow the secure fitment for safe removal.CHROME MOLYBDENUM SOCKET – This is hard-wearing, tempered and anodised for corrosion resistance.DURABLE THIN-WALLED DESIGN - For use with impact tools.DOUBLE-ENDED 6-POINT SOCKET – This is externally sleeved to prevent damage to alloy wheels and nuts.SOCKET SIZES - 18.5 x 19.5, 19 x 21, 21 x 21.5, 22 x 22.5mm with a 75mm 1/2"Sq Drive Extension.