AquaLock 81902975 Stackable Stem Tee Push-to-Connect Fitting 1/2" CTS

The AquaLock 81902975 is a 1/2" CTS Stackable Stem Tee push-to-connect plumbing fitting, also known by the SeaTech model number 3533-10. Designed for fast, tool-free installation, this fitting connects 1/2" CTS Stem x 1/2" CTS x 1/2" CTS and is ideal for building compact plumbing manifolds when combined with AquaLock Stackable Elbows.

Compatible with a wide range of tubing materials, the 81902975 accepts connections from Copper, CPVC, PEX, LDPE, MDPE, HDPE, and Polypropylene tubing — making it one of the most versatile quick-connect tee fittings available. The fitting's stainless steel gripper ring resists corrosion and locks securely to multiple pipe materials without tools.

Key Features:

• Stackable design — pairs with AquaLock Stackable Elbows to build distribution manifolds
• Push-to-connect — no tools required for installation or disconnection
• Rotates under pressure — full rotation under system pressure for flexible positioning
• Stainless steel gripper ring — corrosion-resistant, locks to Copper, CPVC, PEX, and more
• Patented O-ring guide — protects the O-ring during installation and prevents dislodging
• Size: 1/2" CTS (Copper Tube Size) on all three ports
• Max Temperature: 180°F @ 100 psi / 75°F @ 250 psi
• Also sold as SeaTech 3533-10

A trusted choice for marine, RV, and residential plumbing applications, AquaLock fittings are certified for potable water use and are the number-one choice for boat builders and marine distributors worldwide.