The GS1AV34 is a TeSys GS fuse cover interlock kit, rated for 4 poles at 160 A. It is a locking accessory designed to prevent access to the fuse carrier while the circuit is live — a standard safety interlock for fused disconnect switches in TeSys GS enclosures.
The GS1AV34 belongs to the TeSys range, Schneider Electric's long-running family of motor control and switchgear components. Its category listing as a world service part for control accessories confirms it was originally intended as a field-replaceable spare for installed TeSys GS fused disconnectors. The 160 A rating matches the fuse size for a 4-pole load-break switch in that series.