The two-channel pump head lets you pump two synchronous flow channels, proper retention requires the use of the same size tubing in each channel. These pump heads accept the six L/S precision tubing sizes L/S 13, L/S 14, L/S 16, and L/S 25. Achieve flow rates of 0.06 to 1000 mL/min¿flow rate depends on drive rpm and tubing size.