I'd like to pick up a UL day pack or waist pack.

I should be able to carry 1L of water and lunch for 2-3 people. Maybe 6lbs? So the bag should be 5L+

Prioritizes

#1 Weight.
#2 If day pack must have 2 shoulder straps
#3 Don't need any frills just a simple one pocket bag.
#4 < $100. Bounce points if under $50. Triple bonus points if < $35.

I was looking at the Sea-to-summit Ultra-sil. Its less than 2.4 ounces which is good but on the lager side at 20L. Was hoping for something smaller / lighter.

Suggestions?
Here is the StS.
https://www.rei.com/product/867165/sea-to-summit-ultra-sil-daypack