Quick Answer
Shower filters differ by form factor (inline, filtered showerhead, handheld) and by media (KDF, activated carbon, vitamin C, calcium sulfite, multi-stage). The right type depends on your shower setup, what you want to reduce, and how often you can replace the cartridge.
Problem
The category is full of jargon — form factors, media types, stage counts. Without a map, shoppers buy on stage count alone, which is not a reliable quality signal.
Product Recommendation
ZOOSHEN's range spans inline, filtered-showerhead, and handheld formats with different media. Use the product finder or compare tool to match a system to your water.