From what I've read, 4001's lost the checkerboard binding sometime in April of 1973. They lost the horseshoe/toaster pickups sometime around July/August of 1973. Sadly - for me - my '73 4001 was made in October...

However... if you bought your '74 new, it still would have come with the Maxima flats; which, again from what I've read, didn't have a reputation for wearing out quickly. In fact, I still have a suspicion that the nasty, dirty, raggedy silk flats that were on my 4001, were the original factory flats. While they were definitely a biohazard, they still tuned up; intonated; and played just fine. I'm still bummed about throwing them away... But, yeah, the Rick factory rounds? I have used them - especially the Light Nickel Rounds - and while they were pretty nice (for rounds), they didn't win any prizes for longevity. And, like a lot of factory strings, most of Rick's strings were - and still are - made by D'Addario, although SIT makes them, too.... Because I liked the sound of the Maxima flats that I learned to play bass on, my '01 4003 wears the Optima RB clones. Because my 4001 is starting to suffer that neck problem that they sometimes develop, I had very low tension Dogal Jaco Carbonsteel Flats on it. But, I took them off when I decided to sell it. The buyer will get it with a set of Hybrid Slinkys on it - which, to tell the truth? Don't sound too bad on there...