Abstract: A golf club device, more specifically a putter (1), comprising a head (2) and a shaft (3) attached to the head (2), the free end of the shaft (3) possibly being provided with a grip, wherein the moment of mass inertia of the head (2) constitutes less than seventy-nine per cent of the total moment of inertia of the putter (1) when the putter (1) is rotated about an axis of rotation (4), which is perpendicular to the longitudinal axis (7) of the shaft (3) and about one hundred and twenty centimeters from the longitudinal axis (5) of the head (2), and/or wherein the mass of the shaft, including a possible displaceable weight (11), divided by the length of the shaft is at least one hundred and seventy grams per meter of shaft in a shaft which is up to one meter long, and at least one hundred and ninety grams per meter of shaft in a shaft which is longer than one meter.

Abstract: A golf club head (21) for a putter, in which the club head (21) is provided with a toe wing (31) projecting from a toe portion (23), and a heel wing (31?) projecting from a heel portion (25), each of the wings (31, 31?) being provided with an outward side surface (37) diverging in a direction away from a striking face (27), the toe wing (31) and the heel wing (31?) being connected to one or more bracing means (65, 71, 71?, 73).

Abstract: A golf club device, more specifically a putter (1), comprising a head (2) and a shaft (3) attached to the head (2), the free end of the shaft (3) possibly being provided with a grip, wherein the moment of mass inertia of the head (2) constitutes less than seventy-nine percent of the total moment of inertia of the putter (1) when the putter (1) is rotated about an axis of rotation (4), which is perpendicular to the longitudinal axis (7) of the shaft (3) and about one hundred and twenty centimetres from the longitudinal axis (5) of the head (2), and/or wherein the mass of the shaft, including a possible displaceable weight (11), divided by the length of the shaft is at least one hundred and seventy grams per metre of shaft in a shaft which is up to one metre long, and at least one hundred and ninety grams per metre of shaft in a shaft which is longer than one metre.