Glad you could join us.
Just a couple of things... If your gun is original, I'll bet that it is actually Nickle Plated, not Chrome. Also, the hammer and trigger are probably color case hardenend, but sometimes it can look a little like it's faded or patina'd blue. "CTG." is an abbreviation for Cartridge. Your Regulation Police is chambered for the .38 S&W Cartridge. Not to be confused with the more common and modern .38 S&W Special Cartridge.
With that serial number, the tables in the Standard Catalog of Smith & Wesson by Mr. Jim Supica and Mr. Richard Nahas suggest an early post WW1 manufacture date. your gun was built before the introduction of heat treated cylinders, a process that began around 1920-21 or so, at about serial number 20,000. According to Mr. Roy Jinks, S&W Historian, Regulation Police No. 28,465 shipped in July 1924.