These are Ultra High Flow Tee couplings for 3/16" and 1/4" ID tubes.
Made of zinc plated brass for improved corrosion resistance.
Barbed on all 3 sides
The coupling is 1.5" long.
New! Also offered in "maxiflow" regular size: 3.3 mm ID for 1/8" ID Tygon tubing. This size is 0.2 mm larger in ID than 1/8" to reduce flow turbulence at the fitting.