The PL-259 is a standard connector for HF and lower coaxial cabling. Losses become more pronounced as you go above 30MHz, but it is still usable into the 6-Meter band (around the mid-50MHz range). The PL-259 uses a threaded connector to attach to the SO-259 socket. The PL-259 is the most commonly used coaxial connector in use by Ham Radio operators. When using the connectors, I suggest sticking to the crimp-on style or the ferrule-style versions. When soldering the center conductor to the pin, make sure you completely clean the excess solder and flux off. Flux will cause corrosion quickly, and the excess solder can make a poor connection.