Warton metals omega 6337 rosin free solder wire warton metals 6337 18swg 1 warton metals omega 6327 rosin free cored solder wire is made from a flux core contained in high purity cored solder wire omega solder contains no rosin colophony resin acids pine oil or other naturally occurring derivatives from pine trees and has been specially designed to reduce the number of world wide cases of industrial asthma related to rosin usage within a cored solder wireomega provides excellent