".38 S. & W. SPECIAL CTG" serial number 520xxx
It's chambered for the standard and common .38 Special cartridge.
To date it I need to known if it's a 5 shot or 6.
Serial numbers ran from D90001 in 1969 to D330000 in 1970.
About $300 tops in fair.
on the bottom it has d1111xx
Same answer as above ^^^.
You can shoot 38 special and 38 special +p.