I have 2 Zpacks Arc Blast Top side pockets, they attach to your pack and give you a few extra liters of storage space. I originally bought these with my pack but found I don’t really ever need the extra space so they are still in great condition. According to Zpacks they weigh .5 oz each, so 1oz for the pair. Normally cost 45$ for the pair without shipping costs included. feel free to ask me any questions. I can email pictures.