These universal joints are made of hardened chrome vanadium steel, and the surface is chrome plated and polished for corrosion resistance and long service life. The maximum bending angle of the universal joint can be almost 90 ̊, So this is more suitable for working in a narrower space. These universal joints are finely machined to meet and exceed ANSI/ASME standards to ensure they will fit on any compatible tool. To attach the socket drill extension, snap the end of the adapter onto your drill. Each extender has a spring-loaded ball at the attachment point that locks the socket securely into place to prevent slipping and dropping. It includes one 1/4-inch, 1/2-inch, and 3/8-inch extension socket that fits as a drill socket adapter. Universal joint as an angle conversion tool, cannot be used as a connective rod vertical downwards. Steering angle should be less than 35°, otherwise, edge will be worn fast and inner shaft head will be dropped out easily. Stronger bonding parts for more reliable use.Full 360 degree swivel feature allows use to easily access odd angles and hard to reach areas. Features: Material：Chrome vanadium steel Model：1/4-Inch drive, 3/8-Inch drive, 1/2-Inch drive Szie:1/2 12.5mm*2.9in, 3/8 9.5mm*2.2in, 1/4 6.3mm*1.6in Package content: 1PCS 1/4Inch drive universal joint 1PCS 3/8Inch drive universal joint 1PCS 1/2Inch drive universal joint