OTTO Excavator Parts Is55Us 3Ab1 Cylinder Head Cover Gasket 9113120346 911312-0346 9-11312034-6 For Isuzu OTTO Isuzu IS55US 3AB1 Cylinder Head Cover Gasket 9113120346 – Premium OEM replacement for IS55US 3AB1 mining excavators. Engineered for narrow-site vibration, high temps & oil contact, outlasting cheap aftermarket gaskets. Perfect seal stops oil leakage, protects engine, slashes downtime for nonstop small-scale mining work.