Tusk Tec-Core Battery with Acid TU1-32 Maintenance-Free -Fits: Yamaha RHINO 660 4x4 2004-2007 Premium quality batteries designed to meet the high demands of the power-sports industry. Advanced lead/acid core technology ensures dependability and longevity. Leak-proof cap and seal. 6 month warranty. Complete with acid pack that makes filling simple and accurate.