The entire lock is self-contained within the one-half inch plug diameter.
                                   It includes two parallel rows of six pin tumblers with each row acting
                                    independently with its own side bar. The equivalent of two side bar locks in a
                                    one-half inch cylinder! Each side of the lock is operated separately by each half
                                    of the dual-bladed key. Both the lock mechanism and the key forming process
                                    are patented worldwide. Only the factory and authorized BiLock Service
                                    Centers can duplicate the keys.

              Every BiLock cylinder consists of a plug, 2 sidebars, 8, 10 or 12 pin tumblers and springs, and a cap that holds
              the pins and springs in the plug. There are only15 different pin tumblers, all of the same size and shape. Four
              are common pins which accept only one depth of cut in the key each (e.g., a #1, 2, 3 or 4 depth cut). The
              common pins have a second dummy hole to frustrate picking. The other eleven pin tumblers are master pins
              that will accept from 2 to 4 depths of cut on the key.


 When the key is inserted in to the lock. the pin tumblers are properly located
 to form a shear line on each side of the lock. This allows the spring-loaded
 sidebars to locate the deep holes on the pin tumblers, and to retract so that
 the lock can be turned to the open position. When the key is returned to the
 locked position and withdrawn, the spring-loaded side bars are forced into
 the slots in the lock body &shyp; which places the cylinder in the locked
 position. In the locked position, all pin tumblers rest on the bottom of the
 keyway, making it impossible to read the combination or impression the key.
 

                    Essential to the BiLock system is the unique dual-bladed, "U" shaped key. Each side of the key is cut
                    differently and engages its own set of pin tumblers and side bars. The key blank is originally uncut in
                    a 90° form. There are no key blanks of this type available anywhere else in the world. The uncut
                    blank can only be cut and formed with proprietary equipment at the factory or at an authorized
                    BiLock Service Center. The blank is cut to code on both sides and then formed into the "U" shape
                    &shyp; a patented process. The colored key head (18 different colors) is then inserted and crimped
                    securely into place.

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