The control range is quite wide, at the input 16.73 V, at the output 1.256 - 16.73 V. But the adjustment is very, very sensitiveive when cornering, it spans the entire range for a quarter of the available turn, and then an additional 3 quarters of a turn shows a maximum of 16.73
I used this module to bring battery voltage down from 20VDC to 12VDC for handheld bosch drill machine. Once it came to heavier work the module gave up. Game over.