Hello Paul,
Thank you for your interest in our product.
Here is a recommendation to you:
Part number: #180080
DROK DC-DC Adjustable Buck Voltage Converter Stabilizer 6-32V to 1.25-32V LCD Display Constant Volt Amp 6V 12V 24V Step Down Voltage Regulator Power Module with USB Port Protective Shell

Parameters：
Input voltage: 6~32V
Output voltage: 1.25~32V (Input must be 1.5 higher than output.)
Output current: Max.5V, adjustable, recommend the use of within 4.5A. (Over 2A or 35W, please enhance heat dissipation.)
Constant current needs above 2V output voltage, then can be adjusted. Only in the status of constant current can current adjustment work.
Output Power: Max. 75W (recommend the use of within 50W, please reduce power if the dropout voltage is large)
Operating temperature: -20 ~+70℃
Operating frequency: 180KHz
Conversion efficiency: up to 96%
Short circuit protection: Yes
Input reverse polarity protection: None
Over-temperature protection: Yes (Automatically shut off the output when over-temperature.)
Connection: terminals or solder terminals; VIN is input; VOUT is output
Module dimension: 65.6 x 40 x 25mm

Voltage-calibration Method:
In the case of power off, press and hold the “SET” key and power on, then enter into voltage calibration mode, and LCD screen starts to flash, release the “SET” key;
press “SET” and “ENT” key to increase or reduce the voltage to the right input voltage. It will automatically saves after 2s, then power off and the calibration is complete.

Current-calibration Method:
Suitable for no-load with current display or slightly large current. In the case of power off, press and hold “ENT” and power on, then enter into current calibration mode and LCD screen starts to flash, release the “ENT” key; press “SET” and “ENT” key to increase or reduce the voltage to the right value. It will automatically saves after 2s, then power off and the calibration is complete.

Please note that if you want to use this product in your application, you need to enhance heat dissipation.
Hope this can help you.
Best regards

Hello Paul,
You’re welcome.
Could you please send us the product link of DROK FJ40D12A10 so that we can ensure which product?
Best regards

Hello Paul,
Thank you for your reply.
We have checked this part number you sent to us but we cannot find out the product.
This number may be just the part number of one of the component.
So it is hard for us to ensure the product.
Could you please ask your colleague to send the product link to you of the ASIN?
With your help, we can find a solution more quickly.
Hope you can understand.
Best regards

Hello Paul,
Thank you for your continued patience.
For the parameters you need, this product is suitable for your application.
But you have mentioned that taking into account any current surge, which we cannot ensure if it is work your application.
If there is a large current, it will burn the product.
Hope this can help you.
Best regards

Hello Paul,
You’re welcome.
If there is any question, please feel free to contact us.
Have a nice day!
Best regards