The 3K55 Bastion is a modern coastal defense system of Russian origin. It was developed in the 1990's as a possible replacement for the 4K44 Redut system and for export sales. The NATO designation for the Bastion is SS-C-5 Stooge and it is possible that in Russia the system is referred to as 3K55 Oniks. The 3K55 Bastion is based on the 3M55 Oniks missile, which is also used on ships and aircraft.

The Bastion is a mobile coastal defense system that consists of several vehicles. A typical battery would include four launch vehicles, a command vehicle, a radar vehicle and several maintainance and transloader vehicles. The launch vehicles are based on the MZKT-7930 8x8 chassis. Three missiles are carried per vehicle and stored in a large box with two large doors that cover the roof. The command vehicle is based on the Kamaz 43101 6x6 truck chassis and may control up to 12 launch vehicles.

The Bastion launches the large and powerful 3M55 Oniks missile, which is known in the West as the SS-N-26 Strobile. The ground launched variant has a maximum range of 300 km on a high altitude flight profile and 120 km when sea skimming all the way. Due to the Mach 2.5 speed and sea skimming abilities the 3M55 is very difficult to intercept. Since the missile is dependent on radar data the range is limited to the effectiveness of the coastal radar systems.

The Bastion system relies on radar data for plotting the flight path of the 3M55 missile. The three types of radar systems that may be used are exsisting coastal radars, special targetting helicopters and mobile radar systems. The system that is most likely to be used with the Bastion is the vehicle mounted Monolit-B radar that has a passive range of 150 to 200 km and active range of 35 to 70 km.

The whole Bastion system is mounted on cross country trucks and is able to cross allmost any terrain, albeit at limited speed when off road. The setup time of the launch vehicles and the Monolit-B radar system are as low as 5 minutes, allowing immediate action upon halt.

The sole confirmed user of the Bastion system is Vietnam, although it may also be in limited use with Russia. Syria has reportedly ordered the Bastion for delivery beyond 2010.