Abstract: A device for attachment to a golf tee comprises a first marker to be aligned with the intended direction of travel of a golf ball and a second marker which lies generally normal to the first marker and which is intended to be aligned with the face of a golf club with which a golf ball supported by the tee is to be struck. The device includes an aperture through which the shank of a golf tee can pass to enable the device to be selectively attached to the golf tee. The device also includes a platform formed with a plurality of angularly spaced radially extending line indicators separate from the boundary of the aperture which enables the first marker to be offset from a true line to counteract inter alia a natural slice.