When successfully deployed, an MLM produces smoke for 30 minutes, and then the canister sinks and degrades. The MLM body is made of aluminium which corrodes rapidly in salt water. The intact plugs near the base of the MLMs shown here indicate that they are duds or misfires. If an MLM fails to fire or is prematurely extinguished, it can float and eventually wash ashore. Most dud/misfire MLMs found on the beach are likely to contain all, or some portion, of their original chemicals, and can be dangerous if mishandled.