The Leica M10 Thumb Support is an accessory grip that offers improved ergonomics for the Leica M10. Key features include:

Compatibility. This thumb support has been designed and shaped specifically for use with Leica M10. While it may physically fit on other camera models, it won’t technically line up correctly with the controls.

Improved Ergonomics. The M10’s slim profile makes it slightly more difficult to securely hold than previous digital Ms. The M10 Thumb Support offers a more steady and secure grip, even allowing one-handed shooting for those times you can’t put your smartphone down…

Hot-Shoe Mounted. The thumb support slides into the M10’s hot shoe. This means no other device can be used in the camera’s hot-shoe like flashes, electronic viewfinders, etc.