What is the maximum printing size for a single pass? The maximum print height is 14.29 mm/0.5625 inches. For a single print, it can print up to 1.3m/4.26ft long. In multi-line printing mode, it can print up to 3m/9.8ft. If you want to print larger patterns, you can use the multi-line function to stitch them together with the help of rulers. Typically, how often do I need to refill or replace ink cartridges? A single ink cartridge can print up to 415 full pages (A4), enough for a year of daily use. If you need to replace the ink cartridge, you can purchase the corresponding ink cartridge on our official website. How long does ink last on shirts and other washable items? The print lasts a long time until you wash it or it gets soaked with water or sweat which washes off the ink. If you want to print permanently, we recommend you to use our Fixtant, use it before printing, it is waterproof and permanent. How is the working time/battery life? Princube integrates a 900 mAh battery. It can print continuously for 6 hours on a single charge and stand by for 1 year. How to fully charge? Normally 2 hours. It can print continuously for 6 hours on a single charge and stand by for 1 year. Can I print on metal/glass? Yes, you can print on metal/glass. Can I use HP ink cartridges instead of yours? Yes, it is also compatible with HP62 and HP804 color ink cartridges (support standard and XL, and HP64, but the color arrangement is not as good as HP62 and HP804). Can this printer print on black surfaces? or white? It is possible to print on a black surface, but if the base color is too dark, the colors will not show up perfectly. Printing white is not supported. The printer cleans itself regularly to avoid clogging, how about yours? We recommend that you clean the ink outlets at least once a month. When not in use, it is best to close the lid. By the way, there is a cleaning function, support you long press the button, it will print 3-color lines, let you know the printing status in advance. How long is the shelf life of the ink? Ink cartridges have a shelf life of 18 months. If it is a used ink cartridge, stored properly in the right environment, it may last 18 months (15 - 30)