JST SM - Male Housing (4 pin)
This is a 4 pin JST SM Male housings. They're type SM and do require additional parts to turn them into a complete plug / connector.
NOTE : It is possible to crimp the terminals without using the proper crimping tool- You can just use a small pair of wire cutters to bend the terminal arms onto you wire, or you can solder the wire onto the terminal. Neither solution is recommended, but they do work fine for non-critical applications where you only need to make up a few assemblies.