A vascular closure device , comprising: a deployment assembly that is elongate along a longitudinal direction and that has a distal end and a proximal end spaced from the distal end in a proximal direction that is aligned with the longitudinal direction; a sealing unit carried by the deployment assembly, the sealing unit including a suture coupled to the deployment assembly and a toggle attached to the suture and disposed at the distal end of the deployment assembly ; a tamper carried by the deployment assembly and disposed along the suture with respect to the sealing unit in the proximal direction, the tamper including a lumen that receives the suture such that the tamper is slidable along the suture ; and a locking assembly coupled to the tamper so as to selectively inhibit advancement of the tamper along the suture in the distal direction toward the sealing unit , wherein the locking assembly is adapted to transition from A) a locked configuration where the tamper is inhibited from sliding along the suture , into B) an unlocked configuration where the tamper is slidable along the suture in the distal direction and into contact with the sealing unit , wherein the vascular closure device is characterised in that the locking assembly includes at least one tab , the at least one tab including a respective opening that is sized to receive the tamper therethrough, wherein the at least one tab is moveable from a first position, where the tamper is inhibited from the sliding along the suture by the at least one tab such that the locking assembly is in the locked configuration, to a second position, where the tamper is slidable with respect to the at least one tab and along the suture such that the locking assembly is in the unlocked configuration. a deployment assembly that is elongate along a longitudinal direction and that has a distal end and a proximal end spaced from the distal end in a proximal direction that is aligned with the longitudinal direction; a sealing unit carried by the deployment assembly, the sealing unit including a suture coupled to the deployment assembly and a toggle attached to the suture and disposed at the distal end of the deployment assembly ; a tamper carried by the deployment assembly and disposed along the suture with respect to the sealing unit in the proximal direction, the tamper including a lumen that receives the suture such that the tamper is slidable along the suture ; and a locking assembly coupled to the tamper so as to selectively inhibit advancement of the tamper along the suture in the distal direction toward the sealing unit , wherein the locking assembly is adapted to transition from A) a locked configuration where the tamper is inhibited from sliding along the suture , into B) an unlocked configuration where the tamper is slidable along the suture in the distal direction and into contact with the sealing unit , wherein the vascular closure device is characterised in that the locking assembly includes at least one tab , the at least one tab including a respective opening that is sized to receive the tamper therethrough, wherein the at least one tab is moveable from a first position, where the tamper is inhibited from the sliding along the suture by the at least one tab such that the locking assembly is in the locked configuration, to a second position, where the tamper is slidable with respect to the at least one tab and along the suture such that the locking assembly is in the unlocked configuration. <EOS>