Profile: Convertech, Inc. produces shafts. Our equipment includes air roll lock differential shafts, concentric shafts, continuous lug shafts, lateral motion shafts, mechanical shafts, small diameter shafts and through shafts. Our air-roll-lock differential shaft is suitable for a full range of converting and web production operations. We design continuous lug shafts, which feature 1.5" to 16" diameters, face lengths to 150", aluminum or steel bodies and aluminum, steel or urethane lugs.