На испуг, Na ispug, literally "for fright"), was a Soviet improvised fighting vehicle, based on an STZ-5 agricultural tractor, manufactured in Odessa during the Siege of Odessa in World War II.

[1][3] When the army fighting on the outskirts of Odessa (the city defences held out for seventy-two days before the army pulled back) started experiencing shortages in tanks, the workers from the factory decided to build a fighting vehicle of their own design.

The armour was a sandwich of thin naval steel or boiler plate and wood or rubber sheeting to improve protection against small arms.

[7] These then fought during the siege against the Axis forces in support of Soviet troops.To reinforce and replace losses this in turn created NI tanks.

[8] 68 NI tanks (all but one) were captured by the Axis-aligned Romanians by the end of the siege,[9] with 14 still being on hand as of 1 November 1942.