LOW VOLTAGE LED DIMMER or DC TO PULSE WIDTH MODULATOR

I had a question or I can dim or have slower run with LOW VOLTAGE LED DIMMER (mk187) or DC TO PULSE WIDTH MODULATOR (K8004)?

Features engine:

DC electric motor
Voltage: 14.4 volts
Current: 4 to 4.5 amps

The K8004 (DC to PWM) is more universal for this.