The Sears PM 31 has been discontinued. However, you can still buy the same battery. Odyssey manufactured it for Sears, so the identical battery is the Odyssey 31M-PC2150.Madgaffer, I believe that the X2 31 series battery from Batteries Plus that you bought is a rebadged Northstar. It has a greater reserve than the Odyssey. Excellent battery and good warranty. If I ever go AGM, I would be putting that X2/Northstar in my boat.Last edited by catdude28 on March 4th, 2016, 4:11 am, edited 1 time in total.