A putter-type golf club comprising an alignment system and a club head assembly. The putter-type club head has a body that is preferably composed of aluminium, with a rear weight disc and small inserts composed of a material denser than the material used for the remainder of the club head (excluding inserts in the “wings” on the club head and/or the neck of the club). The body has an alignment channel that is approximately the same width as a standard golf ball, and which runs from the face to the rear of the club head. In a preferred embodiment this alignment channel is black or dark in colour with a white or light-coloured border. The putter-type club has a neck that is inserted laterally through the side of the club head, such that it runs parallel to the face of the club head and for substantially the length of the face.