This is the W-86. You've probably never heard of it but it's basically an F-91 that's better in every way but oneor maybe two.
Casio Illuminator W86 — LATEST REVIEWS — Ben's Watch Club
Casio W86: The true successor to the F91W?
How the legendary Casio F-91W won my heart
Casio F105 vs W86 - Which is the true F-91W successor?
Casio F-91W or Casio W-86-1VQES?
Casio W-86 or F-91W?
The Big Bad Brother: Casio W-86
Get this EL gem before they stop making it
Casio W-86-1V Review & Unboxing
Casio W86 vs F91 (and why I'm sticking with the F91 despite the improvements)