to their compactness and small number of parts. Excellent reassembly characteristics provide superior speed. The use of spacers with the coupling permits easy mounting and dismounting without the necessity of moving heavy machinery. This is helpful in the replacement of seals and bearings in pumps and other equip- ment. 16 8 2 7 49 10 5 3. 5 6 CONSTRUCTION OF FORM-FLEX COUPLINGS .