Survival rafts contain water sensors which trigger the compressed air cylinder to inflate the raft. To prevent against accidental inflation, a small magnet and reed switch is placed in the raft. The magnet needs to be pulled out of its pocket for the unit to activate when it hits the water. Reed Switches are also used in emergency locator transmitters (ELT) to prevent the unit from transmitting when inside the cover. This is done by placing a magnet inside the pocket of the cover and mounting a reed switch inside the ELT. This keeps the ELT from transmitting as long as it is inside its cover. Suitable products: MS-10x miniature PCB mountable reed sensors, R3 miniature SMD reed sensors.