1S91 SURN vehicle included two radar station – a target acquisition and distribution radar 1S11 and a continuous wave illuminator 1S31, in addition to an IFF interrogator and an optical channel.
While 1S31 antenna was installed on the upper section of the superstructure and the 1S11 on the lower, they could turn around independently. To make the height of the vehicle lower the central cylinder was able to hide inside the prime mover.
The acquisition range of the radar was reported as 50 km for the Phantom II type target.
Total weight of the 1S91 vehicle with a crew of 4 was 20.3 tonnes and 2P25 vehicle with 3 missiles and a crew of 3 was 19.5 t.