Here's a KIT for FIELD MORTISING Perfect Lock Bores on BEVELED AND SQUARE EDGE Doors . WORKS ON 1-3/4" and 1-3/8" THICK doors. Your Lock Prep WiLL look like FACTORY in a SNAP !! Use the 2-1/8" Bit to Bore Holes from BOTH SIDES. Use 1" BIT to BORE LATCH Hole. Use the 5/16 bit to drill (2) lever holes if required. CHOOSE 2-3/4" BACKSET or 2-3/8" BACKSET STANDARD KIT includes (1) LOCK BORING JIG .... ALL bits ...2 CLAMPS AND A CARRYING BAG. Professional Crafted Set for The Door and Hardware PROFESSIONAL !! Of COURSE it's MADE in the USA !!! Look at the Pictures to see how everything works !!