Casio G-Shock GA-B2100 CasiOak vs Tissot Gentleman Powermatic 80 Silicium

Casio's design language vs Tissot's approach

The Casio G-Shock GA-B2100 CasiOak features a Carbon Core Guard Resin case at 45.4mm (48.5mm lug-to-lug, 11.9mm thick) with Mineral Glass protection. The Tissot Gentleman Powermatic 80 Silicium offers Stainless Steel construction at 40mm with Sapphire Crystal. Both represent their brand's distinct design philosophy and heritage.

Quartz Module 5689 (Tough Solar + Bluetooth) vs Powermatic 80.811 (Silicon Hairspring)

The G-Shock GA-B2100 CasiOak runs the Quartz Module 5689 (Tough Solar + Bluetooth) (Casio Quartz (Solar-Powered), About 7 months on a full charge without light; about 18 months in power-saving (Casio) power reserve) at standard frequency. The Gentleman Powermatic 80 Silicium uses the Powermatic 80.811 (Silicon Hairspring) (ETA-Based Automatic with Silicon Hairspring, 80 Hours reserve) at 21,600 vph (3 Hz). The Gentleman Powermatic 80 Silicium offers a longer power reserve.

45.4mm (48.5mm lug-to-lug, 11.9mm thick) vs 40mm — different wrist presence

At 45.4mm (48.5mm lug-to-lug, 11.9mm thick), the G-Shock GA-B2100 CasiOak has a bolder wrist presence compared to the Gentleman Powermatic 80 Silicium at 40mm. Water resistance differs: 200m (20 ATM) vs 100m (10 ATM).

Casio sits in the lower tier

The Casio G-Shock GA-B2100 CasiOak sits at $100–$150 and the Tissot Gentleman Powermatic 80 Silicium at $500–$1,000. On the specs that outlast any price: the G-Shock GA-B2100 CasiOak uses Mineral Glass with About 7 months on a full charge without light; about 18 months in power-saving (Casio), against Sapphire Crystal and 80 Hours on the Gentleman Powermatic 80 Silicium. Service intervals are typically 5-7 years for both.

200m (20 ATM) vs 100m (10 ATM)

The G-Shock GA-B2100 CasiOak is rated to 200m (20 ATM) while the Gentleman Powermatic 80 Silicium handles 100m (10 ATM). The G-Shock GA-B2100 CasiOak is better suited for water activities.