chrome vanadium stainless steel, with a flexible shaft spring. The use for traditional fixed extension is not suitable for places. Apply to all handheld ratchet applicationsEasy accessRely on bent extensions to quickly loosen bolts and nuts for light torque in awkward corners and hard-to-reach areas. Flexible and StrongTightly coiled steel springs allow you to achieve awkward angles of up to 45° while maintaining high torque transmission. It makes your installation more flexible, convenient and efficient. Flexible Design Spring-loaded ball locks to prevent sliding parts for machines with square drive radius corners to reduce tool and bushing wear. Chrome vanadium steel anvil and anvil, chrome-plated mirror, made of spring steel and PVC sleevesHOLD mode safetyA drive head on a ball fastener allows you to securely latch the seat without dropping or deformation. Multiple Size OptionsFeaturing three drive sizes such as 1/4 (6.35mm), 3/8 (10mm) and 1/2 (12.5mm) for maximum versatility is a great addition to any tool kit. Package Included: 1 Set Thank you for your attention, you can for more details about the goods. Welcome to visit. I hope you have a nice day!