This is Strathearns magnum size (true magnum size) lace weights designated as D5. I had originally classified these weights as a PSM213DS to follow the other Strathearn lace weight designations but a friend recently bought a book on paperweights and inside the book was a Strathearn brochure dated May 1974, and which he very kindly sent to me, and now for the first time I have the official Strathearn number designation for this weight series. I have no information as to when these were first produced, if they were made in any quanity or when they were actually discontinued but you'll see below examples for possibly 1967/69 signed only by an S cane, 1969, 1970 and 1971. Perhaps these were the only years any were made and maybe not...only time will tell but this D5 designation does not show up in any of the later year brochures that I have past 1974. Most of these are over 3.5" but under 4.0" in diameter but one #4516 is a huge 4.2" in diameter and within this catagory I've classified this one as a super magnum.