Casio G-Shock G9000 Mudman Band EASY Replacement! - YouTube
User manual Casio G-Shock G-9000-1VER (English - 4 pages)
Casio G-Shock MUDMAN 3031 G-9000MS - YouTube
I bought a bunch of Casio from a recycling company. Under them was this vintage DW-9000 (in near mint condition). New battery and it's runs flawlessly. I paid 40€ for 11 watches,
Casio G-Shock Mudman 3031 G-9000 Army Military Green Watch | eBay
Casio G-Shock G9000-1V (3031) Men's Mudman Digital Black/Orange | eBay