Abstract: A modular golf club head system provides a hosel adapter that can be attached to the club head at different rotational positions to selectively change the loft or lie angle of the club head. The club head defines a hosel ball socket, and a locator pin extends from the socket. The hosel adapter has a shaft end configured for connecting to a golf club shaft, and a distal end including a hosel ball inserted into the hosel ball socket. The hosel ball defines at least one first locator pin recess and at least one second locator pin recess. The locator pin recesses formed in said hosel ball at differing angles, wherein insertion of the locator pin into the first locator pin recess defines at least one of the loft and lie angle of the club head, and insertion of the locator pin into the second locator pin recess defines a different loft or lie angle of the club head.

Abstract: Disclosed is a putter including an interchangeable sleeve mechanism capable of easily replacing and mounting a shaft, the putter comprising a main body part, a downward extension part, a blade formation part having a plate-shaped structure which extends to a predetermined length rearward from a lower end of the downward extension part and has an area having a predetermined size, a plurality of weight mounting grooves disposed to be spaced a certain interval from each other in an upper surface or a side surface of the blade formation part and configured to bind weights in a detachable structure, and a sleeve mechanism mounted in a structure detachably attached to the binding groove of the main body part, having a block structure extending to a predetermined height upward, and formed with a shaft binding fastening hole recessed to a predetermined depth in an upper end surface.

Abstract: A putter head includes a forwardly facing putting face extending in a longitudinal direction between a heel end and a toe end, and the putter head includes a front part and a rear part. The front part includes: a forward-facing surface including the putting face and a slot provided in an upwardly facing surface of the front part. The slot is configured to take up a hosel for connecting a shaft to the putter head and to arrange the hosel at different longitudinal positions between the heel end and toe end of the putter head. The slot includes a bottom surface, and a rearward-facing surface. The rear part includes an upward-facing surface having connecting means for connecting one or more weights to the rear part of the putter head at different longitudinal positions between the heel end and toe end of the putter head.