Tie, and the anon poster are correct. There have been at least three persons killed because of the sweat and electric radios being plugged in. So only batteries it has been for many years. Nothing new, just not been enforced in many locations.
As for the dewalt, I used to carry one in the package car. STrapped it right under the diad holder, and the strap also went through the right hand rail, and the foot rail around the heater. Never moved from there.
Good for about 20+ hours on a single charge, I would recomend the 18 volt battery, 85 bucks at lowes, but it lasts and lasts, and has a 3 year warranty. If it goes dead before then, take it back for a new one.
It takes a beating and gives pretty good sound.
As for anything you listen to that you have in both ears, they are not allowed, as your hearing will be limited, and the loose cord can get caught in machinery. Sorry, that too is against safety rules at UPS. You might be able to use only one, in one ear, but the cord can not be loose. Check if it would be allowed.
I have seen drivers with one or both earbuds. To me, that would really be an issue, especially if involved in an accident.
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