Amazon.com: DROK Voltage Regulator DC 8-60V to 10-120V 15A Boost Converter, Constant Voltage Current Step Up Module Adjustable Output 48V 24V 12V DC Power Supply with LED Display : Electronics
DC DC Buck Converter 8V 160V 96V 84V 72V 60v 48v 36v Step down to 5V 9V 12v 15V 19V 24v Voltage Regulated USB Power Supply CAR|Replacement Parts & Accessories| - AliExpress
24V DC Power Supply (homemade/DIY)
120VAC to 12VDC Power Supply - CircuitLab
DC to DC converters
12 V to 30 V High Current Boost Converter Circuit [Variable] - Homemade Circuit Projects