Sky, I wonder why they didn't think about the right hand positive batteries. I see both versions here and try to stock the 300 CCA version of both. Matter of fact the way some mower battery cables are setup only the right config will work as the cables are too short otherwise.
Besides the U1 and U1R there is a U2 version out there which is slight shorter in length and height. But there is a
link on the U1 where you can find a U1 up to 525 CCA. It is also to note that the industry is phasing out the old wet cell version in favor of the AGM (Adsorbed Glass Mat) and Gel-Cell versions along the Lithium version. Now the AGM and Gel-Cell version do have a slightly different re-charge rates as my current battery charger is setup to do (ie lower voltage).
Personally I have found most AGM batteries are higher in cost as it newer technology. Most my current experience with the AGM batteries is the ATV/UTV vehicles but some of it is from the electronics industry too. Many are smaller in size then the U1 size and still pack a lot storage. What we got to pay attention to is the 20 hour aH ratings along with CCA ratings.
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