The P-18-2 “Prima” (Russian designation: 1RL131-2, Cyrillic: П-18-2 «Прима», 1РЛ131-2) is a highly mobile surveillance and target acquisition radar operating in the VHF band. The crew consists of two men. The set-up and take-down time are only 5 minutes each.

The P-18-2 is a successor to the P-18. The radar is fully transistorized and uses intrapulse modulation. The antenna elements are very similar to the antennas of the predecessor type. Therefore it can be assumed that the same frequency range of 150 to 180 MHz is used.