John Guest vs SharkBite vs AquaLock Push-to-Connect Fittings

John Guest vs SharkBite vs AquaLock

Choosing between push-to-connect fittings? At Specialty Sales, we stock the three brands customers ask about most: John Guest, SharkBite, and AquaLock (formerly SeaTech). They're all push-to-connect fittings, but each one is built for a different job.

Quick Rule of Thumb

• Plastic tubing for water treatment, RO, or potable water? John Guest 

• Copper, PEX, or CPVC rigid pipe for household or commercial plumbing? SharkBite 

• RV or marine plumbing? AquaLock 

John Guest

John Guest is our largest push-connect vendor and the go-to choice for plastic tubing applications. If you're running polyethylene or nylon tubing in water treatment systems, RO systems, potable water lines, or food-grade applications, John Guest is built for the job. 

• Fittings come mostly in acetal (gray) and polypropylene (white or black), with brass and stainless steel options in select products like half cartridges 

• Inserted and removed by hand, with no tools and no release step 

• Sized by the OD (outside diameter) of the tubing 

SharkBite

SharkBite is the one to reach for when you're working with rigid pipe such as copper, PEX, CPVC, and other pipe types, whether in stick form or coiled rigid pipe. It's a lead-free brass fitting, owned by Reliance Worldwide Corporation (the same parent company as John Guest). 

• Works with copper, PEX, CPVC, and other rigid pipe types 

• Approved for behind-the-wall and underground installations 

• Uses a release tool to disconnect, and is not designed for frequent connect and disconnect cycles like John Guest 

• Sized by CTS (Copper Tube Size), which is based on the pipe's ID (inside diameter) 

A note on sizing: when you see "1/2 inch" or "3/4 inch" on a SharkBite fitting, that's the ID of the pipe. John Guest, on the other hand, sizes by the OD of the tubing, so it's worth knowing which convention you're working with before ordering. 

AquaLock (Formerly SeaTech)

AquaLock is similar in use to SharkBite. It works with copper, PEX, and CPVC, but it's a plastic fitting and is specifically marketed to the RV and marine industry. Many customers still know it as SeaTech, which was the brand name before Watts acquired the company and rebranded it. 

• Plastic construction 

• Works with copper, PEX, and CPVC 

• Specifically built for RV and marine applications 

Need Help Choosing?

We stock all three lines, so whichever one fits your job, we have it. If you're still not sure which fitting is right for your application, contact our sales team! They know all of these lines well and can walk you through it.