Peachtree Multi-Joint spacing system is for making three different sizes of box joints.(1/4; 3/8; and 1/2 inch joints. It also will make sliding dovetails and Off-Set rabbet joints. The three jigs are 24 inches long and 5-1/2 inches wide. Set-up is easy as brass set-up blocks are provided. The manual is well written and very detailed with many photos.