Siemens 672-600 ACTUATOR REBUILD KIT, COMPOSITE DISC, WATER MIXING, 3-WAY, 1/2" LINE SIZESiemens 672 600 Actuator Rebuild Kit, Composite Disc, Water Mixing, 3 Way, 1 2" Line Size This Actuator Rebuild Kit is Flowrite 591 Series and includes spring seat, thrust washer, thrust bearing retainer, adjustable screw assembly, stem lock nut, copper slug, bonnet lock screw, housing retaining screws and holding retaining nuts, for 1 2" line size.