I have a blued Mod. 29-5 "29 Classic" with a 6.5" full underlugged barrell. It does not have ANY serial number in the normal area when you open the cylinder/yoke. DOES have the "Mod. 29-5" stamped designation, AND it has "69D" electrically engraved on the inside of the yoke, like it might have been very carefully engraved by a gunsmith, but it is BLUED, that is, the engraved 69D was done before the gun or yoke was blued! I have never seen the like! It is a round-butt frame and on the bottom of the the grip frame it has BFL9486 very neatly stamped or maybe etched. On the grip frame, side plate side, down by the bottom of the frame it is factory engraved or stamped 90374 (space) 690. Also has some inspector marks on the lower side of the grip frame, on the latch side, like a big Q in a circle followed by BX6. Barrell says in gold "Smith & Wesson" on one side and "29 Classic" on the other. Came w/ Hogue grip. Looks like a 1995 or so gun which I bought a year or so ago. No lock. What is the Deal with the S/N!!! Never seen a 'Smith like it! All Help Appreciated! Thanks - MR