and this, you say?
http://www.ebay.com/itm/390839159132
[
b]5A DC-DC Adjustable Buck Step Down Module 24V/12V/5V Voltage Regulator Converter[/b]
Module features:Module Properties: non-isolated step-down module (BUCK)
Input voltage: 4-38V
Output voltage:1.25-36V continuously adjustable
Output current :0-5A (recommended for use within 4.5A)
Output power: recommended for use in below 75W, more than 50W please add heat sink.
Working temperature: -40 to +85 degrees
Operating Frequency: 180KHz
Conversion efficiency: up to 96%
Load regulation: S (I) ? 0.8%
Voltage Regulation: S (u) ? 0.8%
Short-circuit protection: Yes (the limited current is 8A)
Over-temperature protection: Yes (automatic shutdown when over-temperature)
Input reverse polarity protection: No, (if necessary, please string into the high current diode)
Installation: two 3mm screws
Wiring: Welding, V-IN is the input, V-OUT is the output
Dimensions: 54* 23*18 (mm)