ul - What approval is required on custom made retail electronic items for sale in the USA

I have a custom built retail display unit + wall mount/table top unit, which I wish to sell to retail shops in the USA.

Retail display unit

1. It is powered by 24V DC, external power supply



2. Internally 24V DC is converted to 240V AC 50 Hz by inverter (Mean Well Inc.)


3. It has professional grade display screen powered by 240V AC 50 Hz


4. It has 24V DC to 5V DC SMPS (Mean Well Inc.)


5. Standard brought out SBC has HDMI port for display


6. Custom built interface board has low power RF 2.4 GHz network card for interfacing with "wall mount/table top unit"

Wall mount/table top unit

1. It's body built using acrylic sheet material


2. It is powered by 24V DC, external power supply



3. It has single/multiple 125 KHz RFID readers (custom built)


4. My custom SBC has serial port for RFID reader interface and low power RF 2.4 GHz network card for interfacing with "retail display unit"

What certifications are rrequired for both units?

Do I have to have a UL approval as well?