Penn Plax Small World Pet Supply. Pet Supply » All Pet Products » Tropical Fish » Ponds » Accessories » Equipment » Filter » Filter Cartridges Filter • Filter Pads Filter • Foam Inserts Filter • Filter Resins Filter • Filter Sleeves Filter • Filter Carbon Penn-Plax Small World Replacement Filtration Units 2-pack buy bestselling pet products, supply find reviews, ratings, prices Price: $3.09 Features • for swf-1 • 2-pack [ + Zoom ]   [ Buy Now ] Pet Products : Usually ships in 1-2 business days Non User