Hoya 4x Cross Screen Star Effect Glass Filter - 52mm — Glazer's Camera
APEC Water Systems CS-Series 5,000 Gal. Replacement Filter for CS-2500P Under-Counter Water Filtration System with Scale Inhibitor FI-CS-2500P - The Home Depot
WD-CS Wet / Dry Filter System (Filter with Overflow Box) Eshopps WD-150CS - Glass Aquatics
Playing With Lenses: Filter Hoya 49mm CS (Cross Screen)