A toothbrush including a handle forming a gripping portion of the toothbrush and a replaceable brush head carrying a plurality of bristles, wherein the replaceable head is connectable to the handle in a detachable manner by means of a snap locking mechanism (13, 14), the snap locking mechanism including a finger protruding from the handle and a recess formed in the brush head, wherein the finger extends along a longitudinal direction, wherein the finger includes a flexible portion and a non-flexible portion that are integral to each other and that are configured to be at least partly received in the recess when the brush head is mounted on the handle; wherein the non-flexible portion connects the flexible portion to the handle; wherein the flexible portion is configured to elastically flex away from the bristles with respect to the non-flexible portion in a direction transversal to the longitudinal direction during the insertion of the finger into the recess along the longitudinal direction, wherein the flexible portion is configured to flex due to the interaction with an inclined surface formed in the recess during insertion of the finger into the recess along the longitudinal direction, wherein the flexible portion includes a protrusion configured to snap into an engagement position with the recess when the protrusion slides beyond the inclined surface inside the recess, wherein the recess is open on a back side of the replaceable head opposite to the bristles, wherein the non-flexible portion includes two lateral ribs on opposite sides of the finger configured to slide and engage into corresponding grooves formed in the recess during the elastic flexing of the flexible portion, characterized in that said lateral ribs do not extend to the flexible portion. wherein the replaceable head is connectable to the handle in a detachable manner by means of a snap locking mechanism (13, 14), the snap locking mechanism including a finger protruding from the handle and a recess formed in the brush head, wherein the finger extends along a longitudinal direction, wherein the finger includes a flexible portion and a non-flexible portion that are integral to each other and that are configured to be at least partly received in the recess when the brush head is mounted on the handle; wherein the non-flexible portion connects the flexible portion to the handle; wherein the flexible portion is configured to elastically flex away from the bristles with respect to the non-flexible portion in a direction transversal to the longitudinal direction during the insertion of the finger into the recess along the longitudinal direction, wherein the flexible portion is configured to flex due to the interaction with an inclined surface formed in the recess during insertion of the finger into the recess along the longitudinal direction, wherein the flexible portion includes a protrusion configured to snap into an engagement position with the recess when the protrusion slides beyond the inclined surface inside the recess, wherein the recess is open on a back side of the replaceable head opposite to the bristles, wherein the non-flexible portion includes two lateral ribs on opposite sides of the finger configured to slide and engage into corresponding grooves formed in the recess during the elastic flexing of the flexible portion, characterized in that said lateral ribs do not extend to the flexible portion.