Circular comb for a combing machine for combing textile fibres, comprising a base body with a centre longitudinal axis, a peripheral surface and two end faces, a plurality of bar tacks, which are arranged on the peripheral surface of the base body and define a combing region of the circular comb, a plurality of fastening devices attached to the base body for the non-positive connection of one of the bar tacks in each case to the base body and unlocking units to release the non-positive connections, each unlocking unit having an unlocking device and an unlocking means to actuate the unlocking device, wherein the unlocking units are accessible from outside the combing region, in particular from at least one of the end faces, and an additional positive securing connection to secure the bar tacks is provided on the base body.