Low Flow Single Tube Rotameter

The 1/8" FNPT Model P Flow Meter is engineered for low flow-rate precision, delivering the simplicity, versatility, and cost-effectiveness of a classic rotameter in a rugged, ready-to-install package. Ideal for chromatography carrier gases, manufacturing process control, and dependable liquid or gas measurement in laboratories, pilot plants, and flow/level indication applications, each unit ships fully assembled with standard mounting fittings, protective side plates, a thick magnifying front shield, and flow tubes. High-precision control valves are especially valuable for ultra-low flow ranges that require high sensitivity. Model P 65mm and 150mm flow meters include air and water flow data; flow data for routine gases is available on the spec sheet. These meters feature enhanced readability and durable construction, ensuring reliable performance across various industries, including healthcare, food and beverage, biotechnology, and water treatment. The OPTIGRAD™ scale design minimizes parallax & reduces eye fatigue during long monitoring periods. See spec sheet for flow data for routine gases.

  • Designed specifically for low flow-rate accuracy, sensitivity, & repeatable measurement
  • Integrated magnifier lens improves readability & enhances resolution
  • Easy flow tube installation and exchange for fast range changes & streamlined maintenance
  • Non-rotating adapter feature prevents glass tubes from turning during tightening/assembly
  • Optional high-precision control valve for extremely fine adjustment at very low flow rates
  • Chemical compatibility supported through multiple float & sealing material options
  • Simple panel-mounting method supports clean integration into OEM systems & lab setups
  • Built with precision-ground floats for consistent, stable, & accurate flow indication
  • Pressure rating: 200 psi/13.8 Bar
  • Maximum temperature: 250ºF (121ºC)
Item # Description Catalog Pg. Price Add to Cart
65mm Aluminum Single Tube Rotameter w/ High Precision Valve, Air: 19mL/Mn
Item 97724
213/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
213/Each
65mm Aluminum Single Tube Rotameter w/ High Precision Valve, Air: 49mL/Mn; Water: 0.5mL/Mn
Item 97725
213/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
213/Each
65mm Aluminum Single Tube Rotameter w/ High Precision Valve, Air: 145mL/Mn; Water: 2.3mL/Mn
Item 97726
213/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
213/Each
65mm Aluminum Single Tube Rotameter w/ Standard Valve, Air: 216mL/Mn; Water: 3mL/Mn
Item 97727
140/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
140/Each
65mm Aluminum Single Tube Rotameter w/ Standard Valve, Air: 538mL/Mn; Water: 11.7mL/Mn
Item 97728
140/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
140/Each
65mm Aluminum Single Tube Rotameter w/ Standard Valve, Air: 1036mL/Mn; Water: 20mL/Mn
Item 97729
140/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
140/Each
65mm Aluminum Single Tube Rotameter w/ Standard Valve, Air: 2520mL/Mn; Water: 70.5mL/Mn
Item 97730
140/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
140/Each
65mm Aluminum Single Tube Rotameter w/ Standard Valve, Air: 4917mL/Mn; Water: 143mL/Mn
Item 97731
140/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
140/Each
65mm Aluminum Single Tube Rotameter w/ Standard Valve, Air: 12058mL/Mn; Water: 364mL/Mn
Item 97732
140/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
140/Each
65mm Aluminum Single Tube Rotameter w/ Standard Valve, Air: 24452mL/Mn; Water: 723mL/Mn
Item 97733
140/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
140/Each
150mm Aluminum Single Tube Rotameter w/ High Precision Valve, Air: 34mL/Mn
Item 97734
276/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
276/Each
150mm Aluminum Single Tube Rotameter w/ High Precision Valve, Air: 138mL/Mn; Water: 2.25mL/Mn
Item 97735
276/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
276/Each
150mm Aluminum Single Tube Rotameter w/ Standard Valve, Air: 262mL/Mn; Water: 4.9mL/Mn
Item 97736
205/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
205/Each
150mm Aluminum Single Tube Rotameter w/ Standard Valve, Air: 816mL/Mn; Water: 19.2mL/Mn
Item 97737
205/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
205/Each
150mm Aluminum Single Tube Rotameter w/ Standard Valve, Air: 1665mL/Mn; Water: 44.3mL/Mn
Item 97738
205/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
205/Each
150mm Aluminum Single Tube Rotameter w/ Standard Valve, Air: 4494mL/Mn; Water: 132.5mL/Mn
Item 97739
205/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
205/Each
150mm Aluminum Single Tube Rotameter w/ Standard Valve, Air: 7720mL/Mn; Water: 234mL/Mn
Item 97740
205/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
205/Each
150mm Aluminum Single Tube Rotameter w/ Standard Valve, Air: 16493mL/Mn; Water: 498mL/Mn
Item 97741
205/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
205/Each
150mm Aluminum Single Tube Rotameter w/ Standard Valve, Air: 23105mL/Mn; Water: 579mL/Mn
Item 97742
215/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
215/Each
150mm Aluminum Single Tube Rotameter w/ Standard Valve, Air: 60212mL/Mn; Water: 1972mL/Mn
Item 97743
215/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
215/Each
65mm Stainless Steel Single Tube Rotameter w/ High Precision Valve, Air: 19mL/Mn
Item 97744
408.16/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
408.16/Each
65mm Stainless Steel Single Tube Rotameter w/ High Precision Valve, Air: 49mL/Mn; Water: 0.5mL/Mn
Item 97745
408.16/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
408.16/Each
65mm Stainless Steel Single Tube Rotameter w/ High Precision Valve, Air: 145mL/Mn; Water: 2.3mL/Mn
Item 97746
408.16/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
408.16/Each
65mm Stainless Steel Single Tube Rotameter w/ Standard Valve, Air: 216mL/Mn; Water: 3mL/Mn
Item 97747
278/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
278/Each
65mm Stainless Steel Single Tube Rotameter w/ Standard Valve, Air: 538mL/Mn; Water: 11.7mL/Mn
Item 97748
278/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
278/Each
65mm Stainless Steel Single Tube Rotameter w/ Standard Valve, Air: 1036mL/Mn; Water: 20mL/Mn
Item 97749
278/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
278/Each
65mm Stainless Steel Single Tube Rotameter w/ Standard Valve, Air: 2520mL/Mn; Water: 70.5mL/Mn
Item 97750
278/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
278/Each
65mm Stainless Steel Single Tube Rotameter w/ Standard Valve, Air: 4917mL/Mn; Water: 143mL/Mn
Item 97751
278/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
278/Each
65mm Stainless Steel Single Tube Rotameter w/ Standard Valve, Air: 12058mL/Mn; Water: 364mL/Mn
Item 97752
278/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
278/Each
65mm Stainless Steel Single Tube Rotameter w/ Standard Valve, Air: 24452mL/Mn; Water: 723mL/Mn
Item 97753
278/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
278/Each
150mm Stainless Steel Single Tube Rotameter w/ High Precision Valve, Air: 34mL/Mn
Item 97754
473.16/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
473.16/Each
150mm Stainless Steel Single Tube Rotameter w/ High Precision Valve, Air: 138mL/Mn; Water: 2.25mL/Mn
Item 97755
473.16/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
473.16/Each
150mm Stainless Steel Single Tube Rotameter w/ Standard Valve, Air: 262mL/Mn; Water: 4.9mL/Mn
Item 97756
349/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
349/Each
150mm Stainless Steel Single Tube Rotameter w/ Standard Valve, Air: 816mL/Mn; Water: 19.2mL/Mn
Item 97757
349/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
349/Each
150mm Stainless Steel Single Tube Rotameter w/ Standard Valve, Air: 1665mL/Mn; Water: 44.3mL/Mn
Item 97758
349/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
349/Each
150mm Stainless Steel Single Tube Rotameter w/ Standard Valve, Air: 4494mL/Mn; Water: 132.5mL/Mn
Item 97759
349/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
349/Each
150mm Stainless Steel Single Tube Rotameter w/ Standard Valve, Air: 7720mL/Mn; Water: 234mL/Mn
Item 97760
349/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
349/Each
150mm Stainless Steel Single Tube Rotameter w/ Standard Valve, Air: 16493mL/Mn; Water: 498mL/Mn
Item 97761
349/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
349/Each
150mm Stainless Steel Single Tube Rotameter w/ Standard Valve, Air: 23105mL/Mn; Water: 579mL/Mn
Item 97762
359/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
359/Each
150mm Stainless Steel Single Tube Rotameter w/ Standard Valve, Air: 60212mL/Mn; Water: 1972mL/Mn
Item 97763
359/Each
Save 5% when you buy 2+
Save 10% when you buy 4+
Save 15% when you buy 12+
NEW
359/Each

Note: Product testing for individual applications is recommended before use. U.S. Plastic Corp. cannot be held liable for individual application failures.

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