Mechanics: Non-Sealed Needle Bearing or Bushing. Part Number: RP124 (435502), RP125 (435503)|Weight: 3.95 lbs (435502), 4 lbs (435503)|MBS: 25,000 lbs (111kN)|Rope Capacity: 5/8"|Side Plates: Stainless Steel|Mechanics: Bushing (435502), Bearing (435503)|Sheave: (2) 4" Aluminum|Axle: Stainless Steel|Size (in): 9x4.75|NFPA Version: Exceeds tests for national fire protection association standard on fire service life safety rope and system components NFPA 1983-2006 edition. *Not Certified*