New Singer class 401 / 401A Slant-o-Matic sewing machine service manual. This is a high quality reproduction of the original adjusters manual, it features clear text and illustrations. The handy coil binding allows it to sit flat on your work surface or be folded back-to-back. This invaluable booklet contains extensive adjustment instructions, wiring diagrams, plus multiple parts diagrams and the numerical parts lists. Measures 8 1/2" x 11", 44 pages, coil / spiral bound.