The Sony FDA-EP4AM Eyepiece Cup is for the Sony Alpha DSLR-A900 and DSLR-A850 digital cameras. It is a replacement eyecup that was originally included with the camera.
If your camera's eyecup was lost or damaged, this is the replacement you need. It is a soft-touch eyepiece cup that will protect your DSLR camera's viewfinder from dust and moisture, and help block out unwanted light from your viewfinder.
FDA-EP4AM Eyepiece Cup (replacement)