MasterGear v4.9 for Windows is released. MasterGear is a program that emulates 8bit SEGA videogames on your computer. It runs games made for SEGA MasterSystem (Mark3 in Japan) and GameGear, as well as their predecessors: SG1000, SC3000, SF7000, and Mark2. MasterGear will also help hobbyists who still write software for these systems to debug their works without using rare and costly development hardware.

MasterGear v4.9 for Windows Changelog:
Fixed audio randomly not working on MG-Windows startup.
Added "Video | Show Framerate" menu option to MG-Windows.
Most command line options should now work in MG-Windows.
Increased synchronization timer precision in MG-Windows.
Added "-fps" command line option to MG-Linux.
Added "-4x3" command line option to MG-Linux.

Download: MasterGear v4.9 for Windows
Source: Here