No other option on this list will last as long as the Wahl beard trimmer, which comes packed with a giant battery, an impressively fast recharge, and lots of useful attachable combs, which will also do your hair.
Specifications of Wahl Beard Trimmer for Men
Trimmer length range: 0.2-25mm in 0.5mm increments
Accessories: Eight attachable combs, four close-trim attachments, beard comb, storage pouch, blade oil, cleaning brush
Battery life: 180 minutes
Charge time: 1 hour
There are 12 different combs to help guide your shaving (lengths ranging from 0.2-25mm). And if you need a closer shave, just take off all the combs and get a precision shave with the standard blade.