140J8 Poly-V rib belt. 8 Ribs. 14” (356mm) O.C. – PJ356 Metric belt. Industrial GRADE “J” Series Poly-V (Micro V) ribbed belts are designed to replace OEM belts on extra heavy-duty applications such as 140J8 sander/planer belts, compressor belts, 140J8 (8-Rib PJ356) fitness drive belts, and electric motor drive belts. AKA: J8-140 Belt.