Hiltron or Spectrum E31T2V1 / E31N2V1 / E31U2V1 Cable Modem 2U Rack Mount - Etsy
Motorola V.3229 UDS Rack Mount Modem
Since no one makes a rack mount cable modem I made my own. : r/homelab
AXIOM-N IP-Centric Rack-Mount Satellite Modem
WTI Rack Mount Modem RMM-288DC | eBay
Amazon.com: MULTITECH MT2834BR MODEL# MT2834BR 33.6 V.34 MODEM FOR RACK MOUNT : Electronics
Free Standing or Wall Mount Network Server Rack, Holds All Your Networking It Equipment Router Modem - China Server Rack Holds All Networking It Equipment, Wall Mount Network Server Rack | Made-in-China.com