Application: IHI IHI30NX-2 Mini Excavator Bottom Roller Weight: 17.64 pounds Package Dimensions: 5.51" X 5.51" X 8.26" Material: 50 MnB Steel Surface Hardness: HRC52-58, Deepth:5mm-8mm Locking pin, 65Mn or 45 carbon steel, hardened HRC25-28 Bolt, grade 12.9, HRC45-52. 6 Seal: Nitrile rubber. Operating temperature range -20℃ to 110℃ Finish: smooth Technique: forging and casting Features: 1. This bottom roller is a durable undercarriage replacement part for your excavator 2. Our rollers utilize special high strength-hardened steel and quality seal groups that provide excellent lubricating oil retention 3. Sealed bearings stop dirt, mud, and grime from penetrating inner components 4. It was designed and manufactured to exact OEM specifications using a high-quality, high-strength steel 5. It will provide long-lasting and dependable performance even if you operate in the most extreme conditions