I noticed this on the Amazon.com website today: Warranty, Parts: Optima warrants to the original purchaser that this battery is free of defects in material and workmanship for a 36 month replacement period when shipped and sold by Amazon.com. If a replacement is necessary due to a defect in materials and/or workmanship the battery will be replaced free of charge, within the free replacement period from date of original purchase. Please contact Amazon Customer Service with your warranty claim. For purchases from Amazon Merchant sellers please contact the seller directly for warranty support. So purchasing through Amazon.com should be ok. I'd just have to deal with the hassle and downtime of going through Amazon.com.