The Flipper DeepSee 4″ Viewer is an optical-grade, magnetically mounted magnifier designed for aquarium use. It features a 4-inch viewing portal and offers a focal range of approximately 3 to 8 inches, making it ideal for close-up inspection of fish, coral, and aquatic life. Strong rare-earth magnets allow it to securely attach to glass or acrylic tanks (up to about 16 mm thick). Safe for both freshwater and marine setups, it enhances photography and monitoring by revealing fine detail that’s normally hard to see.