610J8 Poly-V rib belt. 8 Ribs. 61” (1549mm) Length - PJ1549 Metric belt. GATES PREMIUM INDUSTRIAL “J” Series Micro-V ribbed belts are designed to replace OEM belts on extra heavy-duty applications such as 610J8 power tool belts, compressor belts, 610J8 (8-Rib PJ1549) fitness drive belts, and electric motor drive belts. AKA: J8-610 Belt.