The TeSys GS GS1KKG4 is a 4-pole fuse switch disconnector body rated for 125 A conventional free air thermal current. It's the core switching element for a fused disconnect — you add the fuse links and the operating handle separately. The 4-pole configuration handles three-phase plus neutral, or two independent supplies, depending on your circuit layout. Rated operational current hits 125 A at 400 V AC-23A and AC-23B, which covers motor switching with occasional overloads. Breaking capacity is 1000 A at 400 V AC-23B, making capacity 1250 A at the same voltage — that's the fault it can close into without welding contacts. For higher fault levels, the short-circuit making capacity with associated gG fuses reaches 100 kA at 400 V.
The external left-side operating handle means the switch is actuated from the left face, which matters for panel layout when you're stacking multiple disconnects in a row. Power circuit terminals accept bars or screw terminals for 35 to 95 mm² flexible cable; torque to 12 N·m. The TH protective treatment means it's tropicalized for humid environments, which is standard for most industrial panels but worth noting if your site sees condensation.