Game Boy Cartridge Pokemon Green with Case Operation confirmed & internal battery replaced, so data saving is confirmed to be possible without issue. However, please understand that as this is an old item, we cannot guarantee all operations. Thank you for your consideration. We offer bundle discounts, so please take a look at our other Game Boy related items. Please note that this item is also listed on other sites, so we apologize in advance if it is sold out due to a timing conflict.