Phoenix Contact 1205121 A screwdriver specifically designed for use with test socket screws features a unique, pre-drilled hole pattern that allows for secure fastening in place, typically featuring a combination of male and female threads to prevent tampering or tamper-evident design, and is available in various sizes but generally fits one size, characterized by its hexagonal (six-sided) head and measuring 0.6 inches wide, 3.5 inches long, and 100 mm in overall length, providing a comfortable grip through a textured surface that prevents slippage.