This is a Colt 1908 Pocket Hammerless that has an experimental frame. Slide appears to be from the standard production. Machined finish frame is still "In-the-white". Types of stocks are not listed.
Factory letter reads: "Colt experimental frame and magazine with grip safety, main spring and sear. Partially cut-away on left side of frame. Marked on butt "Cal.380/Colt." Magazine front lip at base purposely filed off. Attached tag on which is written in pencil: "Experimental/Grip-safety/ Main Spg./ Sear ' '/ Att. Mr. Stevens."