mtistands forMarine Technologies International. A long name that stands for a brand that specializes in one important thing: designing and building USCG approved life jackets so people can enjoy their time on the water better. Life jackets, also known as PFDs, that are comfortable, have great features, look good on you and are affordable. Above all, MTI jackets are ones that you will WANT to wear. And statistics prove that if you wear your life jacket you will be safer on the water.