How to setup WAN 1 as primary and LTE failover (Vigor2865L Series) – DrayTek FAQ
Teltonika RUT950 Industrial 4G LTE Wi-Fi WAN Failover Router for AT&T, T-Mobile, Rogers, Telus, and Bell - Walmart.com
cisco - Load Balancing and failover on 2 Router 2951 - Network Engineering Stack Exchange
Amazon.com: UTT ER840G 4 Port Internet WAN Router with 4 Gigabit WAN Ports – Load Balance & Failover – VPN – USB – Access Control – for Business : Electronics