As the title of this article suggests, this product is a result of the collaboration of Agency Arms and Sage Dynamics. It is called Modular Magazine Release (MMR) which is a pretty much self-explanatory name. The MMR consists of the main magazine release core and interchangeable buttons of different shapes and extension degrees over the frame.
Without a need to disassemble the firearm, users can change the magazine release button type to better suit the application that they are going to use the firearm in. It will also allow to better fit any particular shooter’s hands by choosing the size that he is more comfortable and efficient with.
Right now they are offering three magazine release button options. The first one (top one on the image below) is almost identical to the factory magazine release. It is just slightly larger and is designed for concealed carry use. The middle one in the image below is a bit more elevated above the frame and it is also extended forward thus having a larger surface area. And the third one has both larger surface and is significantly elevated over the frame. This is basically a competition style button but they intentionally didn’t make it too oversized not to interfere with your normal grip.
Here is a video by Aaron Cowan, who is the designer of this product.
The different buttons are installed by being screwed into the base using an Allen wrench. Right now the version for Glock Gen3 pistols is available on Agency Arms’ website at an MSRP of $59.99. The Gen4 version is in development.