Water Purification Supplies Mb-4021-Xlp Extra Low Pressure RO Membrane 4.0" X 21"

The Water Purification Supplies MB-4021-XLP (part no. 4021-XLP-WPS) is a 4.0" x 21" extra low pressure spiral-wound reverse osmosis membrane element rated at 950 GPD with 98.5% nominal salt rejection. It is designed for low-TDS feed water such as municipal tap water and light brackish water, where it delivers high flow at very low operating pressure to cut pump energy. Supplied wholesale by All For Water.

Specifications & operating limits

• Nominal / minimum salt rejection: 98.5% / 98%
• Permeate flow: 950 GPD (3.6 m³/d), ±15%
• Active membrane area: 39 ft² (3.6 m²)
• Feed spacer: 28 mil
• Test conditions: 500 ppm NaCl, 100 psi (6.9 bar), 77 °F (25 °C), 8% recovery, pH 7 – 8
• Max. operating pressure: 600 psi (41.4 bar)
• Max. feed flow: 3.6 m³/h (15.9 GPM)
• Max. operating temperature: 113 °F (45 °C)
• Max. pressure drop per element: 15 psi (1.0 bar)
• pH range: 2 – 11 continuous, 1 – 13 during cleaning
• Feed free chlorine: <0.1 mg/L
• Max. feed SDI (15 min): 5
• Dimensions: length 21" (533 mm), diameter 3.9" (99 mm), permeate tube OD 0.75" (19 mm), tube extension 1.05" (26.7 mm)

Salt rejection should be verified after 24 – 48 hours of continuous operation; results depend on feed water quality and operating conditions. Request a quote for current wholesale pricing and volume discounts.