this takes about the same time with all "normal and current" power supply units (if that is what was meant?). As the current and voltage are limited and the Noco does not allow "fast" charging. The device actually gives you the answer itself --> 3h, not much can be done about that, except that it can take longer if you use a bad or old charger.
Unlike the new GBX series, this device does not have a fast charging function. It only charges with 5W max. 2 A, i.e. 10W. Pretty much any USB charger can do this. A full charge therefore takes 3 hours.