Spirit level for mounting of components that are to have a particular fixed angle to the horizontal, e.g. window sills, whereby the lower longitudinal surface is at a given angle to the upper, bubble incorporating, surface

摘要

Spirit level has two non-parallel long sides and two angles (1, 2) that are not right angles. The lower side of the level is at a special fixed angle to the upper side, which incorporates the bubble element, and the length of the spirit level is dependent on that of components that are to be mounted.