Finally got my SGW-300H working again! A simple battery reset did the job. : r/casio
1 Pc Silicone Watch Strap Stainless Steel Buckle Sport Breathable Wristband for CAsio W 735H W 800 SGW 300H SGW 400H Watch|Smart Accessories| - AliExpress
Gents Casio Digital SGW-300H Twin Sensor Sports Watch - 100m | eBay