sentences:  Introduced on 20 December 1939, the Panzer Badge was authorized for award to tank crews who had actively participated in three armoured assaults on different days.On 1 June 1940 a bronze version was created for panzer grenadier units equipped with armoured vehicles, as well as other infantry, armoured reconnaissance and medical units serving with Panzer divisions.From 31 December 1942 armoured unit repair teams could receive the silver badge for repairing tanks in combat conditions on three different days.In June 1943 additional Tank Badges were instituted in both silver and bronze to reward participation in "25", "50", "75" and "100" armoured actions.