E-Z Sink is used to cut the funnel shaped impression into the post after drilling with a self-feed bit, to accept the taper of the log rail. This permits the ability to obtain tighter fits on furniture or to give a stronger shoulder fit on rails. This 45º countersink can adjust to flare a 1", 1½", and 2" countersink hole. The E-Z Sink can be used with a 1/2 inch drill motor or the Milwaukee 3/4" Drill. Made in the USA by the maker of the E-Z Tenon Cutter.