The DAN Surface Signal Kit was created to provide peace of mind, and high visibility to divers who find themselves too far from the boat. When fully inflated, the Surface Marker Buoy (SMB) provides a 1.85cm column of High Visibility Orange tubing with a strip of radar reflective material in the center that is easily detectable up to 500 meters away. The kit also includes a long lasting light stick, whistle and signal mirror. This signaling kit will get you noticed when you need it most.