Ideal for all types of dowel joinery, the Task Doweling Jig features four threaded holes to accept hardened steel guide bushings. The jig comes with three pairs of bushings in ¼”, 5/16” and 3/8” sizes. Guide bushing holes are precision drilled and reamed for extreme accuracy. Large steel clamping screw tightens the tool like a vise, with rugged aluminum sides holding work securely without damage to the wood. The patented automatic self-centering action assures accurate center drilling every time, regardless of stock thickness. Will work with stock up to 2-3/8” thick. Additional guide bushings may be purchased separately. Made in USA.