Canon has two different black ink cartridges in the PG510 and CL511 range. The standard capacity ink cartridge has 9ml of ink inside whereas the PG512 has 15ml inside. The standard capacity cartridge has a smaller sponge inside whereas the PG512 has a large sponge inside so it can hold more ink. When buying PG512 refilled or PG512 compatible ink cartridge please beware that some unscrupulous sellers are disguising standard capacity cartridges as XLs by simply putting an XL sticker over the top of the cartridge. We know this is happening industry wide unfortunately on marketplaces such as eBay and Amazon. However there is an easy way you can tell if you really have received an XL cartridge. A PG510 weighs approx 6g less than a real PG512 when filled. A PG512 should weigh approx 50g (without the transport clip) whereas a PG510 weighs 44g when fully filled. If you have received a small standard capacity cartridge when it was advertised as an XL please contact eBay or Amazon customer services by opening a case or an A to Z claim. The seller will obviously try to wriggle out of it claiming it was an error however it's very obvious and these types of mistakes just don't happen with a reputable company. At Office Beaver we ensure we only use the correct cartridge for our Canon PG512 black refilled ink cartridges so our customers can be assured of getting the real thing.