High quality and durable With anti-vibration rubber caps 　　 Bearing Weight: 85 - 170kg made of electro-galvanized, metal sheet, with epoxy spray, no rusty. SP430 Suitable for (BTU): 7000-18000, 20'FT Qty: 7488 sets/20'container SP550B Suitable for (BTU): 24000, 20'FT Qty: 4416 sets/20' container