The 721 means it was imported from overseas, and the shaft and butt were pulled out of the box and matched up before going to whichever store was selling it.
They used to ship huge batches of cues from Asia after Brunswick stopped making cues in the US, with piles of shafts and butts sent in crates. Easy to match up the piles with stamped assembly numbers.
The value is lower than an older model, but they can still be converted so people will pay $150-$200 without breaking a sweat