Whatman application specific filter, activated carbon loaded paper, Grade 72 circles, diam. 47 mm, pack of 100
Amazon.com: 16x48 Cut-to-Fit Activated Carbon Filter Sheet (1 Pack) Multi-Use Charcoal Air Filter Pad for Air Purifiers, Air Conditioners, Air Vents : Home & Kitchen
Carbon-Infused Filter Pad | Activated Carbon Pad for Fish Tank Filters – Aquarium Co-Op