Benchtop pumps with 400D1 single channel pumphead

120U/D1 fitted with 400D1 pumphead

120U/D1 fitted with 400D1 pumphead

400D1 single-channel pumphead with three rollers, accepts continuous tubing only
120 pumps for biopharm, science and research

120 pumps for biopharm, science and research

Exceptional accuracy, combined with a digital display and intuitive user interface, ensure that these pumps are precise and simple to use


120 Peristaltic pumps brochure

120 Peristaltic pumps brochure

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The Watson-Marlow 120S/D1 and 120U/D1 pumps comprise a 400D1 single-channel pumphead powered by a 120 variable speed or automatic drive. The pumphead accepts 1.6 mm wall, continuous tubing in five materials in sizes from 0.5 to 4.0 mm internal diameter. The pump gives flow rates up to 120 ml/min.

120 pumps are small and stackable, saving valuable space in cleanroom, LAF and biosafety cabinet installations.

120S: Manual control, 1-200 rpm in 1 rpm increments. Speed scrolling, priming and keypad lock.

120U: 0.1-200 rpm in 0.1 rpm increments. Manual remote control or automatic control via 4-20mA or 0-10V inputs. Speed scrolling, priming and keypad lock.

  • Flow rates 0.001 to 120 ml/min at 2 bar (30 psi)
  • Compact footprint requires minimal benchtop space
  • Superior speed control up to 2,000:1, ±1% set speed accuracy, repeatable flow
  • Efficient and intuitive to use, requiring minimal key presses
  • 400D1 single-channel pumphead accepts continuous tubing only
  • Smooth, wipedown case with no sharp edges to tear gloves and no bug traps. IP31 ingress protection
  • Maintenance-free, brushless DC motor
  • Three year warranty

Fermentation The 120 is the perfect pump for maximising yield in fermentation and cell culture applications. Ultra-compact and stackable for multiple feeds such as pH control, antifoam, nutrient and buffer addition, the 120 offers the ideal combination of size and technology to optimise your process.

Single-use systems The 120 pump is perfectly suited to single-use systems where no contamination can be accepted. Error-free tube change takes only seconds.

Process validation The biopharm process requires accurate and repeatable pumping which is easy to validate. With an exceptional 2,000:1 speed range, the 120 delivers the flexibility and purity so vital to drug trials. A keypad lock secures your pumping parameters for constant and repeatable performance.


Functionality 120S/D1 120U/D1
Manual control    
1 to 200 rpm (200:1)  
0.1 to 200 rpm (2000:1)  
Numerical speed display
Reversible direction
Max (prime)
Auto start
Remote control    
Run/stop, direction change, auto/man toggle, alarm  
Analogue control    
0.01 to 100 rpm (10,000:1)  
Analogue speed input; 4-20mA, 0-10V  
Tacho speed output; 0-5V  
Keypad lock to protect set-up


Tube bore and flow rates 120S/D1 and 120U/D1 (ml/min)

Speed (rpm) 0.5mm  0.8mm  1.6mm  2.4mm  3.2mm 4.0mm
120S/D1  1 - 200 0.01 - 2.2    
0.03 - 5.8
 0.11 - 23 
0.24 - 49  
 0.41 - 81  0.59 -120
120U/D1  0.1 - 200  0.001 - 2.2         0.003 - 5.8  0.011 - 23  0.024 - 49
0.041 - 81  0.059 -120


400D1 single-channel pumphead

 The single-channel 400D1 pumphead accepts 1.6mm-wall tubing from 0.5mm to 4.0mm.

 This metering pumphead is familiar to users replacing older 101 and 400 series pumps with the 120. Suitable for 120S and 120U drives.


120U offers 0.1 to 200 rpm manual remote control of the pump in 0.1 rpm increments or automatic control in 0.1 rpm increments via 4-20mA or 0-10V inputs.

120S offers 1-200 rpm operation in 1 rpm increments

Datasheet download

Manual download

       120S/D1                  120U/D1 

120S/D1    120U/D1

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