National Diversified Sales 620 Green Plastic Spring Loaded Pop-Up Drainage Emitter for 6" Spee-D Catch Basin connects to the 6" Round Spee-D® Catch Basin Drain (sold separately) to create a high-capacity emitter; also connects directly to 6" drain fittings to discharge collected water conveyed from upstream. The emitter cap pops up to release water when pressure builds. The cap closes once flow diminishes and stays closed when not in use to prevent debris and rodents from entering and potentially clogging the drainage system. The flat profile blends into the surrounding landscape. The Pop-Up Emitter fits on top of the 6" Round Spee-D® Catch Basin Drain and 6" drain fittings. Pop-Up Emitter cap and cover made of high-density polyethylene (HDPE) treated with UV inhibitors. Hassle-free limited lifetime warranty guarantees the NDS product is free from defects—or we’ll replace it.