
Four-prong socket wrenches come in three specifications: 1/4 inch, 3/8 inch, and 1/2 inch. 1 inch equals 25.4MM. Socket wrench classifications: 1. By size (referring to the size of the square drive): 1/4", 3/8", and 1/2" three specifications. " denotes inches, where 1" equals 25.4MM. 2. By length: long socket, short socket, E-type socket. 3. By edges: 6-point, 12-point, 4-point. 4. By appearance: single groove and double groove; knurled; straight barrel; nickel-plated and chrome-plated, etc. 5. By usage: manual socket wrenches and pneumatic socket wrenches (black, chrome-molybdenum steel). 6. By screw type: external hex socket, external Torx socket; internal hex socket, internal hexalobular socket, internal 12-point socket; E-type socket, five-point press-fit socket, five-point hollow press-fit socket, four-point socket, etc.

I've always thought that a complete set of sockets in car tools is quite important, especially the four-claw socket set, which is specifically designed for square screws. When I first bought a car, I didn't understand the sizes and wasted money on the wrong sockets. Later, I learned that a complete set usually includes both metric and imperial specifications, such as the common size range from 6mm to 24mm, with each size representing a specific dimension for easy removal of different-sized bolts and nuts. A full set typically includes over a dozen sockets plus a handle, while cheaper sets might only go up to 19mm, and higher-end ones can cover up to 32mm. When choosing, don’t just look at the quantity; pick the size range that fits the common screws on your car model, otherwise, you might not even be able to remove wheel bolts. I recommend beginners start with a basic 12-piece set—it’s cost-effective and practical.

I've been repairing cars for over a decade and am extremely familiar with the 4-point socket set. The standard complete set comes in two types: metric and imperial. The commonly used metric sizes include intermediate dimensions like 6mm, 8mm, 10mm, 12mm, 14mm, 17mm, and 19mm, while the imperial sizes mainly consist of 1/4 inch, 3/8 inch, and 1/2 inch. Too few sizes might miss crucial screws, while too many waste space. The set I use is a professional 16-piece combination that covers all intermediate values, perfect for engine or suspension screws. Remember, the size affects the socket's depth and strength – too thin might cause stripping. For daily repairs, sizes from 10mm to 19mm can handle most issues.

A while ago, I replaced the spark plugs in my car, and it was all done with a four-claw socket tool set. To be honest, the full set comes in various sizes, with smaller sets ranging from 6mm to 14mm, and larger ones extending up to 24mm or even bigger. I opted for an 18-piece standard set, which includes core sizes like 8mm, 10mm, 12mm, 14mm, and 17mm, along with a handle and a few adapters. The model numbers are just numerical labels without any hidden meanings. The key is to match the sizes commonly used for your vehicle. For instance, small to medium sizes are sufficient for regular family cars, saving you from spending extra on unnecessary tools.


