I ordered two bike batteries from a Chinese company on Ali Express giving them the exact specifications and dimensions of the battery, which the company agreed. Having secured my payment of $554.28, I have received an e-mail stating that the standard size has now changed. I wasted time setting up an e-mail account with AliExpress and time sending e-mails back and forth to the company. I have cancelled my order but fear I may never see this money again. Since ordering I have noticed that this tactic has been used many times on unsuspecting buyers. I am now incredibly worried that the seller will not authorize my cancellation and I will have to go into dispute wasting further time. My experience has meant that I will NEVER EVER trade again with AliExpress. Please read this and learn from my experience and that of many others.