RVR has 10 spots (3 scores each) on the seaming port of the Dome (Top). When the pressure is over the standard level, the scores open to release gas while rupturing the dome, and lowering the inner pressure to prevent an explosion. RVR is a Back-Up Safety Technology Protecting an Unused Can from Over-Pressuring Automatically reseals when removed from stove. Notched Collar provides easier alignment in portable gas burners! Compatible with a diverse variety of camp stoves. Each can lasts approximately 2 to 8 hours of burn time Incredibly compact, lightweight & affordable with a weight of only 8 oz per cartridge. Stronger fuel source than propane Precautions Avoid heat and store in a well-ventilated area at a temperature not exceeding 40 degrees C. For additional precautions, please read the label indicated on the side of the can.