Game Boy Game Cartridge CR1616 Save Battery Holder

Works great for not having to re-solder batteries. However for GBA carts (or at least Pokémon Sapphire), it is just a bit to big even after filing down the plastic as much as possible since it has to sit on top of a chip. Thus the bottom of the GBA cart has a little bit of a gap, but this gap doesn't affect the cart going in or out of the console.
(photo without my finger was after filing down the plastic and one with my finger is before I did any filing)

For my GBA cart I give it a 4 of 5 but for the Game Boy and Game Boy Color carts it would be higher as they have more room.

the plastic makes it slightly too tall so the casing doesnt close quite right and if you press on the cartridge at all while its running it resets the game.

As far as a replaceable battery adapter these things are fantastic. Game boy and game boy color absolutely no problem. Game boy advance on the other hand is a little tight. You definitely want to make sure you have it soldered in flat. The case will bulge a little but still perfectly usable. Not much you can do without trimming the inside of the case though.

Full disclosure: I ordered 8 of these, received 6. Contacted HHL Support and they shipped the missing 2 VERY quickly, even adding the Route shipping protection at their own expense. Their Support Team is Outstanding!! I am semi-experienced with soldering but I was able to remove the old pins from both GB and GBA games and install these battery holders with no problems. For the GB games that use 2025 batteries, these 1616 battery holders work well, you just need to have careful placement to create a solder bridge to the prongs on the holders. Overall, great product and amazing customer service. Will definitely be doing future mods with HandHeld Legends parts!

Bought two of them for my Pokemon Red and Gold version for the Game Boy Color now I can save once again

I just installed these in 12 of my cartridges. I love them. I love that next time I need to replace the save batteries I won’t need to solder anything and I won’t need to buy any special batteries. Some carts barely fit these (carts where the battery contacts sit 45 degrees in relation to the rest of the circuitry) but even those were not difficult to install.