ARRIS SURFboard DOCSIS 3.1 Cable Modem & Dual-Band Wi-Fi Router for Xfinity and Cox service tiers Black SBG8300 - Best Buy
Amazon.com: Motorola MB8611 Cable Modem + AC2600 Smart Wi-Fi Router with Extended Range | Top Tier Internet Speeds | Approved for Comcast Xfinity, Charter Spectrum, and Cox – Separate Modem and Router
From The Wirecutter: The best cable modem (for most folks) | Ars Technica