I found this used Embark brand backpack that is a mere 7.8 ounces. I believe Embark is a Target brand.
It is shown next to an REI Flash 18 for scale. The construction is quite acceptable, with 2" wide webbing shoulder straps, a haul loop/grab handle, nylon zippers, panel loading, a big pocket across the front, bottle pockets on the sides and a hanging pocket inside. The seams are all bound and the back panel is double layer. Judging by the Flash 18 alongside, I would guesstimate the capacity to be about 20 liters. I wouldn't want to haul 20 pounds with it, but it would handle a typical day hiking load of water/snacks/essentials/spare layer with no problem. I didn't see a comparable current model on the Target web site.



Turned inside-out to show the interior side of the back panel:


