Looks like a pre-war (WWII) M&P.
If you remove those aftermarket grips, you'll see the SN (probably on the underside of the barrel and back of cylinder, also). We can tell you a range, within which, it was shipped.
Looks to be a ".38 Special Hand Ejector M&P" shipped between 1915 and 1942. I extrapolate by the number and guess circa 1920. That range runs from #241704 through #700000. The metallurgy from that period is "iffy" regarding the hardening of the steel used. Were it mine, and if I considered it a "shooter", I would shoot only mild, lead wadcutter or lead ball ammo. It will not long endure high velocity or +P loads.
It would look better with a set of vintage "service" grips. I am a hater of rubber grips.