Disclosed herein are methods and devices for restricting the blood flow of an area in a subject. The device includes a restrictor, a bolt and a strip. The restrictor includes a cylindrical body having one open end, one closed end, and a passage there through, in which the inner surface of the cylindrical body towards the open end is treaded and a protrusion disposed on the outer surface of the closed end of the body. The strip is preferably made of an elastic material and is coupled to the protrusion of the restrictor at one end, while allowing the other end (i.e., the free end) to circumvent the area before passing through the passage of the cylindrical body to form a loop that can be tightened to restrict the blood flow of the area in the subject. The bolt has a head and a treaded shaft, wherein the bolt is capable of being driven into the cylindrical body through the open end to engage the threaded shaft of the bolt with the threaded inner surface of the cylindrical body until the end of the threaded shaft of the bolt is held against the strip so as to hold the loop in place and thereby restricting the blood flow of the area.
