Tested by IvyForty liters is the honest size. Big enough for a weekend, small enough to keep you honest.
A week of gear should not take three bags. This large capacity waterproof camping backpack swallows a full loadout through its wide clamshell opening, then carries the weight balanced on a padded mesh back panel with sternum and waist straps pulling their share.
Waterproof build keeps clothes and kit dry through rain showers and wet truck beds.
Wide clamshell opening loads like a duffel and finds like a drawer, no blind digging.
Padded mesh back with sternum and waist straps spreads a heavy load for the long haul.
MOLLE webbing and compression straps cinch the load tight or lash on whatever did not fit.
Paracord-wrapped grab handle survives the yank out of the trunk, trip after trip.
Army Green, one size, $70.20.
Everything for the week on your back, and both hands free for the coffee.