These are the "original 1954 model" or James Jamerson strings, sizes 052, 073, 095 and 110. I bought these new, put them on a 62 reissue P and literally watched the neck bend as I tuned up. Didn't even play one tune with them. Either that bass had a really bad neck, or these strings are just MANLY! I took them off and put them back in their individual sleeves and they've been sitting in my closet ever since. I just bought a reissue Kay bass with a thin neck and I'm positive these strings would snap that puppy like a twig. So no sense in hanging on to them any longer. $25 shipped.