Optima D51R-T1 - this is the thin post JIS version of the Optima D51R. Buy an Optima D51R Battery Online or in-Store with big savings. Optima D51R Pre-Sales advice and technical support. Contact the Store for fitting, charging and installation advice. The Optima D51R is a 12V 450CCA, 41Ah (Amp-Hour) Dual purpose battery (Starting & Deep Cycle). The D51R Optima spiral cell design with the plates wound tightly around a central core gives exceptional vibration resistance (15 times more than most batteries) The Optima D51R is an extremely tough battery, with huge cranking amps for its size. This high starting power, combined with cycling capability (in Yellow Top and some Blue Top's) makes an Optima an excellent choice for many applications. Fast recharging too with its Absorbed Glass Mat (AGM) design. Leak-proof, spill-proof and almost bomb-proof, they are completely maintenance free and can be installed at an angle if required and under-bonnet is fine too. Optima D51R Additional Information. The Optima D51R battery is deemed a non hazardous product for transport use, with no leakage or terminal corrosion. The D51R can be mounted on its side and will not gas under normal charging conditions, ideal for confined spaces in Caravans and RV's.