RKIN Whole House Carbon Water Filter System (CS series)

RKIN's tank-based whole-house carbon filter (CS series). 'CBS 5' is a 5-micron sediment cartridge unit ($359.95), and RKIN's cartridge carbon option is the CBS Dual Carbon Whole House Water Filter ($669.95). Prices are sale prices against compare-at $1,891.80-$3,056.01, with an 'End of Summer Sale' banner promising extra savings auto-applied in cart. Upflow, non-backwashing tank with no drain or power; the carbon must be soaked for at least 2 days and rinsed before install. RKIN warns not to install on well water without checking with them first. 'Certified components' names no standard; no NSF, WQA or IAPMO listing exists for this system (RKIN's only IAPMO file is an RO product). Manual lists pH 6-11, product page 6.5-10; 25-80 psi. RKIN says install is easy with or without professional help and recommends a plumber only if not mechanically inclined. Returns: returnDays is the general 30-day refund window for new, unused items; the advertised one-year guarantee covers days 31-365 but pays store credit minus the 25% restocking fee. Reviews: Trustpilot profile unclaimed with 0 reviews; RKIN's on-site Stamped widget publishes 1,874 reviews, all 5 stars (filters for 1-4 stars return none), so on-site ratings carry little signal. BBB A+, 6 closed complaints in 3 years. Affiliate: Awin, 45-day cookie, commission not published (contact affiliates@rkin.com).