OTTO Excavator Parts Npr75 4Hk1 Valve Spring 8972106826 897210-6826 8-97210682-6 For Isuzu OTTO Isuzu NPR75 4HK1 Valve Spring 8972106826 – 100% genuine OEM excavator part, perfect fit for Isuzu 4HK1 engines. Bulk in-stock, fast global shipping. Superior elasticity & fatigue resistance vs aftermarket springs, cuts rework & returns, boosts resale profits for wholesalers & agents.