Victron Energy Orion 24/12-Volt 25 amp DC-DC Converter Non-Isolated, High Power

The remote on-off connector eliminates the need for a high current switch in the input wiring, the remote on-off can be operated with a low power

Victron DC to DC Chargers & Converters dc-dc 12VDC-12VDC 24VDC 48VDC

Victron Orion XS 12/12-50A DC-DC battery charger [ORI121217040]

Victron Orion-Tr 24/48-2.5A (120W) Isolated DC-DC converter

Third Battery for 12v system in 24v truck setups

Everything You Need To Know About DC/DC Chargers – Energy Connections

Chargers

Buck-Boost DC-DC Converter 25A / 50A / 100A — Intelligent Controls

Orion-Tr 24/12-20 (240W) Isolated DC-DC Converter, ORION-IG-24/12

24/12-Volt 70 amp DC-DC Converter Non-Isolated, High Power

Victron Orion 24/12-70A DC-DC Converter w/Binding Posts - IP20