Abstract: In some embodiments, a cam assembly and strap based closure system using a spiral is configured for bringing two sides of an article together. In some embodiments, when the user inserts the strap into the cam assembly and turns a knob, the strap is driven into the cam assembly and the strap pins engage one or more cam spirals. In some embodiments, the system is configured such that strap pins may be engaged at a constant angle which may be self-locking. In some embodiments, the system may be infinitely adjustable and the torque felt by the knob may be constant. In some embodiments, the system may be configured to be a quick release system and may allow rapid insertion of the strap for faster operation.