The SEC99A UltraCap has a capillary tube that minimizes pressure pulsation. The SEC99A UltraCap has brass-colored flare nuts on the fitting connectors.
The SEC99B UltraTube has a 1/4 in. tube that allows more fluid flow. The SEC99B UltraTube has silver-colored flare nuts on the fitting connectors.
The brass-armored sleeve on all SEC99 Series models provides resistance to abrasion and facilitates routing, coiling, or bending of the capillary or tube. The copper capillary or tube inside the armored sleeve does not effuse refrigerant to the environment. Some models have a breakaway Integral Schrader valve depressor in the flare fitting.