Cyalume ChemLight Military Grade Life-Vest PML Personnel Marker Chemical Light Sticks, Green, 5-1/4" Long, 8 Hour Duration (Case of 50)-US Coast Guard Approved Personnel Marker Light (PML) green chemical light stick with a metal clip for attaching to clothing, lifejackets, or personal flotation devices Provides up to eight hours of 360-degree illumination Can be seen up to a nautical mile away on land, and up to three miles by air Chemiluminescent substance is non-toxic and plastic body is phthalate free for safety Meets U.S. Coast Guard requirements for Approval Series number 161.012/2/1