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Adapters and Connectors

Adapters and Connectors

John Guest ® reverse osmosis & pure water fittings and adapters

See John Guest fitting installation instructions

See Information About Connector & Tube Sizing

  1. JOHN GUEST- PI0212S Union Tee 3/8'' Tube X 3/8''' Tube - 1000
    John Guest PI0212S Union Tee 3/8" Tube X 3/8" Tube X 3/8" Tube
    John Guest PI0212S Union Tee 3/8" Tube X 3/8" Tube X 3/8" Tube Learn More
    $10.99
  2. JOHN GUEST- PI0208S Union Tee 1/4'' Tube X 1/4'' Tube X 1/4'' Tube - 1000
    John-Guest-Tee (John Guest PI0208S Union Tee 1/4" Tube X 1/4" Tube X 1/4" Tube)
    John Guest PI0208S Union Tee 1/4" Tube X 1/4" Tube X 1/4" Tube Learn More
    $9.99
  3. JOHN GUEST- PI201208S- Reducing Union Connector- 1000
    John-Guest-Straight-Connector-2 (John Guest PI201208S Reducing Union Connector 3/...
    John Guest PI201208S Reducing Union Connector 3/8" Tube X 1/4" Tube Learn More
    $8.99
  4. Sea-Tech-Valve-3551-0808-1000
    Sea Tech ® Valve 3551-0808 Quick Connect Fitting For GE Merlin RO System
    Sea Tech ® Valve 3551-0808 Quick Connect Fitting For GE Merlin RO System. Connects the GE Merlin reverse osmosis system to the inlet feed water line. 1/2" in and out. Simple to install. Learn More
    $18.99 Special Price $12.99 As low as $9.49
  5. Sea-Tech-Valve-3550-1008-1000
    Sea Tech ® Valve 3550-1008 Quick Connect Fitting For GE Merlin RO System
    Sea Tech ® Valve 3550-1008 Quick Connect Fitting For GE Merlin RO System. Connects the GE Merlin reverse osmosis system to the inlet feed water line. 1/2" Tube in and out. Simple to install. Learn More
    $21.99 Special Price $14.99 As low as $9.99
  6. Teflon-Tape-100-1000
    Teflon Plumbing Tape To Seal Threaded Water Connectors
    PTFE thread sealant tape permits quick, clean, economical sealing of male pipe threads of all sizes. Reduces the risk of system contamination common with liquid and paste sealants. A must use on all male threads used in reverse osmosis and pure drinking water filtration systems. Learn More
    $2.99 Special Price $2.39
  7. Jaco ® Union Fitting For Poly Tubing
    Jaco ® Union Fitting For Poly Tubing
    Jaco ® Union Fitting For Poly Tubing. Connects two pieces of tube. Learn More
    $8.99 Special Price $4.99 As low as $2.99
  8. Molykote-From DOw Corning- 111 Compound-6 Gram O-ring Silicone Lubricant & Sealant-Dow-111-5-gram-1000
    Dow Corning (Molykote) ® 111 6 gram O-ring Silicone Lubricant and Sealant - Be sure to lube your O-rings to help prevent leaks.
    Dow Corning/Molykote ® 111 6 gram O-ring Silicone Lubricant and Sealant - 6 gram pillow pack. (like a ketchup packet) Great O-ring sealant and lubricant. FDA and NSF approved. (Do Not Use Petroleum Jelly As It May Break Down O-rings Or Housings) This is the same premium grade silicone sealant and lubricant used in underwater photography cameras, scuba gear and other underwater applications that simply can't afford leaks. Why not use the best for your reverse osmosis or drinking water filtration system?

    Dow 111 Silicone MSDS Safety Sheet

    Learn More
    $5.99 Special Price $3.99 As low as $1.79
  9. Dow Corning/ Molykote 111 5 oz. O-Ring Silicone Sealant-1000
    Dow Corning/Molykote ® 111 5 oz. O-Ring Silicone Sealant - Be sure to lube your O-rings to help prevent leaks
    Dow Corning/MolyKote 111 ® 5.3 ounce Tube of O-Ring Silicone Sealant and Lubricant. FDA and NSF approved. Simply the best! (Do Not Use Petroleum Jelly As It May Break Down O-rings Or Filter Housings) This is the same premium grade silicone sealant and lubricant used in underwater photography cameras, scuba gear and other underwater applications that simply can't afford leaks. Why not use the best for your reverse osmosis or drinking water filtration system? Learn More
    $24.99 Special Price $17.49 As low as $16.95
  10. John_Guest_Reducer-3-8-1-4 (John Guest PI051222S Stem Adapter 3/8" Stem X 1/4" MNPT - SOLD IN PAIRS)
    $5.99
  11. JOHN GUEST- PI051223S - Stem Adaptor 3/8'' & 3/8''  NPTF Thread- 1000
    John_Guest_Reducer-3-8-3-8 (John Guest PI051223S Stem Adapter 3/8" Stem X 3/8" MN...
    John Guest PI051223S Stem Adapter 3/8" Stem X 3/8" MNPT - SOLD IN PAIRS Learn More
    $5.99
  12. John Guest Super Speedfit Quick Connector - Male - Straight
    John Guest ® Super Speedfit Quick Connector - Male - Straight
    John Guest ® Super Speedfit Quick Connectors - Male - Straight - MNPT - Sold in pairs. Price is per pair. These fittings are manufactured in gray acetal copolymer with food grade nitrile ‘o’ ring, making them especially suitable for applications involving foodstuff and potable liquids like reverse osmosis drinking water. They are equally suitable for air and inert gasses and can therefore be used on CO2 lines, pneumatic applications, and vacuum. For more than a decade, John Guest has been supplying Super Speedfit fittings to the Water Purification market for drinking water applications in homes, restaurants and industry. John Guest products are listed with the WRC(UK), NSF(US) and SK(Germany). PI010821S , PI010822S , PI010823S, PI011222S , PI011223S Learn More
    $8.99 Special Price $4.99 As low as $3.99
  13. John Guest Super Speedfit Quick Connector - Male - Elbow
    John Guest ® Super Speedfit Quick Connector - Male - Elbow
    ohn Guest ® Super Speedfit Quick Connector - Male - Elbow - John Guest Super Speedfit Quick Connectors - Male - MNPT - Sold in pairs. Price is per pair. These fittings are manufactured in gray acetal copolymer with food grade nitrile ‘o’ ring, making them especially suitable for applications involving foodstuff and potable liquids like reverse osmosis drinking water. They are equally suitable for air and inert gasses and can therefore be used on CO2 lines, pneumatic applications, and vacuum. For more than a decade, John Guest has been supplying Super Speedfit fittings to the Water Purification market for drinking water applications in homes, restaurants and industry. John Guest products are listed with the WRC(UK), NSF(US) and SK(Germany). PI480821S , PI480822S , PI480823S , PI481222S , PI481223S Learn More
    $8.99 Special Price $4.99 As low as $3.99
  14. John Guest water faucet adaptor with quick connector for poly tube
    John Guest ® water faucet adaptor with quick connector for poly tube
    John Guest ® faucet adapter with quick connector for poly tube - Easy quick connect push in installation. 7/16-24 UNS thread to attach to faucet. Cut the end of the tube square ensuring it is free of score marks and burrs. Slip all of the way into and it locks shut. Easy to remove and reuse. 7/16-24 UNS thread to attach to faucet. Choose your tube size. CI3208U7S and CI3212U7S Learn More
    $8.99 Special Price $4.99 As low as $3.49
  15. John Guest ® Straight Union Connector
    John Guest ® Straight Union Connector
    John Guest ® Straight Union Connector - Connects tube to tube using SpeedFit Quick Connectors. PI201208S , PI0408S , PI0412S Learn More
    $9.99 Special Price $6.99 As low as $5.79
  16. JOHN GUEST- PI061208S- Reducer 3/8'' & Stem X 1/4'' Tube- 1000
    John Guest ® Reducer - 1/4" tube to 3/8" stem (pair) PI061208S
    John Guest ® Reducer - 1/4" tube to 3/8" stem. Easily connects 1/4" tubing to 3/8" female quick connect push in fittings. (price per pair) PI061208S Learn More
    $5.99
  17. John Guest Speedfit Plug In Stem Elbow Quick Connector PI220808S, PI221208S, PI221212S, PI221616S
    John Guest Speedfit Plug In Stem Elbow Quick Connector PI220808S, PI221208S, PI221212S, PI221616S
    John Guest Speedfit Plug In Stem Elbow Quick Connector For Water Filtration Systems. Easy to install and uninstall. Simply insert and this plug in eblow will create a 90 degree elbow corner turn. PI220808S, PI221208S, PI221212S, PI221616S. Learn More
    $6.99 Special Price $3.99 As low as $3.39
  18. John Guest inline water shut off valve
    John Guest ® inline shut off valve
    John Guest ® inline shut off valve - Easy to install push in quick connectors. PPSV040808W and PPSV041212W Learn More
    $17.99 Special Price $9.99 As low as $7.99
  19. John Guest ® Tee Connector For water Systems - Quick Connectors
    John Guest ® Tee Connector For Water Systems - Quick Connectors
    John Guest ® Tee Connector - Quick Connectors - All equal size connections or one port different for adaption. The body is produced in acetal copolymer. 'O'Rings are nitrile rubber. The collet is produced in acetal copolymer with stainless steel teeth. PI0208S , PI0212S , PI301208S , PI301612S. Learn More
    $14.99 Special Price $9.99 As low as $7.99
  20. Inline Check Valve - Back Flow Prevention - John Guest Speedfit Quick Connection 1/4SCV and 3/8SCV
    Inline Check Valve - Back Flow Prevention
    Inline Check Valve - Back Flow Prevention - Check Valve- 1/4" quick connect - one way flow, Easy to install. 1/4SCV and 3/8SCV or John Guest Elbow Fitting for Membrane Housing. Learn More
    $27.99 Special Price $19.99 As low as $17.99
  21. John Guest Speedfit Plug Quick Connector. PI0808S, PI0812S, PI0816S
    John Guest Speedfit Plug Quick Connector. PI0808S, PI0812S, PI0816S
    John Guest Speedfit Plug Quick Connector. Use to plug a John Guest Quick Connector filting. PI0808S, PI0812S, PI0816S Learn More
    $4.99 Special Price $2.79 As low as $1.99
  22. JOHN GUEST- 1/4'' Natural/ Clear Poly Tube- Clear Replacement Tubing for Water Filter Systems- 1000
    John Guest ® Poly Tubing For Pure Drinking Water Systems
    John Guest ® Poly Tubing For Pure Drinking Water Systems - 1/4", 3/8" and 1/2" O.D. (Outer Dimension) High Grade Drinking Water Tubing. Speedfit quick connector compatible. Choose the 3/8" O.D. For Use With Optional Drain Saddle For Air Gap Faucet. Sold by the foot. Order 20 to get 20 feet. Learn More
    $0.27
  23. John Guest ® Tube Cutter - TSNIP
    John Guest ® Tube Cutter - TSNIP
    John Guest ® tube cutter TSNIP - Great for making a perfect cut everytime. Helps prevent leaks by making a square end cut ensuring proper fit and seal in water connecttion fittings. A real must for any professional or discerning home owner. Learn More
    $17.99 Special Price $12.99 As low as $10.99
  24. John Guest Tube Cutter Replacement Blades - 5 Pack
    John Guest ® Tube Cutter Replacement Blades - 5 Pack
    John Guest ® Tube Cutter Replacement Blades - Easy replacement. Package of 5 Replament Blades. Learn More
    $15.99 Special Price $11.99 As low as $9.76
  25. John Guest Locking Clips For Speedfit Quick Connectors For Water Tubes
    John Guest ® Locking Clips For Speedfit Quick Connectors For Water Tubes
    John Guest ® Locking clips secure the collet in position on John Guest Quick Connector to prevent an accidental disconnection of the tube. PIC1808R, PIC1812R and PIC1816R. PIC1808R = 1/4 " PIC1812R = 3/8 " PIC1816R = 1/2". Price is for a packet of 10. Learn More
    $7.99 Special Price $4.99 As low as $3.99

Be sure to check our Parts Departmentfor important parts such as TDS Testers, Replacement Tanks, O-rings,Housing Wrenches and more parts for your pure water filtration system.