A head 4 includes a socket 10 and a weight body 12. The socket 10 has an upper hole part 18 and a lower hole part 20. The weight body 12 has an engaging part 32. The lower hole part 20 and the engaging part 32 can be relatively rotated. By the relative rotation, the weight body 12 can take an engaging position EP and non-engaging position NP. The engaging part 32 has an outermost part E1. The lower hole part 20 has a first portion 20x and a second portion 20y. The outermost part E1 can pass through the first portion 20x while compressively deforming the first portion 20x. A distance D2 between the second portion 20y and an axis line Z is greater than a distance D1 between the first portion 20x and the axis line Z.