Penn Plax is a name that stands for Quality, Innovation and Integrity In the Pet Industry for over 50 yearsExperience a great line of Pet Products in all categories! Penn-Plax is committed to creating and manufacturing innovative pet products for first-time pet owners and serious hobbyists alike. FeaturesMedium Sinker HairgrassSinkers are plastic plants with a heavy weight base that will help keep the plant anchored on the bottom for a more realistic look.