Scienceware^® ROTO-FLO^™ flow indicator

Scienceware^® ROTO-FLO^™ flow indicator, fits tubing, 5/16 - 1/2in., green wheel

Scienceware^® ROTO-FLO^™ flow indicator, fits tubing, 1/4 ‑ 5/16 in., red wheel

Scienceware^® ROTO-FLO^™ flow indicator, fits tubing, 3/16 ‑ 1/4 in., blue wheel