The K4108 is 20A and the K4107 is 15A. If it works with about 10A or less, you can replace it. As it is a greater working current, it does not ensure that it works correctly and does not burn.
http://www.datasheetspdf.com/mobile-pdf/647878/ToshibaSemiconductor/K4108.html
http://www.datasheetspdf.com/mobile-pdf/770627/ToshibaSemiconductor/K4107.html