Determining the location of a station in a wireless network including determining path losses between the wireless station of unknown location and at least some access points at known locations. The force applying lever assembly has at least one force applying lever that is coupled to the biasing device or spring of the trap. The clamp has an annular shape configured to surround the hollow anatomical structure in the open position and a flattened shape in the clamping position configured to occlude the hollow interior of the anatomical structure.