A vascular closure system is configured to seal an incision in a vessel of the patient™s body. The system includes a slider that is moved from an initial position to a deployed position (that is, towards the puncture of the patient body), until the proximal end of the slider exposes a reference marker on an inner tube. This 5 confirms the deployment of the closure element and completely expands or opens or pivots the closure element in the blood vessel. FIG. 1A