About Penn Plax: Penn-Plax is a family-owned company in operation since 1959. They specialize in creating excellent pet supplies for animals both great and small. Best known for producing pet products at affordable prices, the Penn-Plax brand is synonymous with innovation and quality, keeping your pet foremost in mind. For cleaning aquarium interiors. Attachments included. Extended reach arm. Simple and easy to use. Penn Plax name.