Works just like the original, maybe even better.

Plays all the master system games I own but on the go

Finding the original Master Gear adapters was difficult and costly. With this I was able to pick up a newly manufactured adapter at a fraction of the cost.
The one I received was complete, solid, fit my system like a glove, and works like a champ.
If you've added a new TFT screen to your game gear and you have some of those old Master System games lying around this is the perfect accessory. Master System games look awesome on the new screens because they natively support a higher resolution.
I've got hours on games like R-Type, Outrun, and Golden Axe.

I'm sure this product works, I just haven't been able to find a quality master system cartridge to test, all of mine do not boot. (I only have a few old ones). That being said mine arrived missing two screws to hold the device together. They do not seem to be very important but that does raise quality concerns. The box and packaging however are superb. Keeping the original packaging will ensure a very long life for this product.