Pls recommend a good no-PWM driver, that accepts 2-cell 8.4V.

Hi, as above. No PWM, current output 2A-3A is ok for XM-L. 3 or 5 mode is ok.

Size is ok, as there is lots of space in the cavity and i do not need to mount it. 3 or 5 mode is ok, but if there is a moddable by bridging contacts beacon or 2Hz strobe then that'd be cool.

update