Here is an inexpensive cotton saddle bag with a large capacity. The dimensions are, 9”L x 9”H x 11”W – 650 cubic inches / 10L. It has a hardwood dowel as an internal support to keep the load stable.
The outer lashing rings are great for securing a wet jacket. The main panel is a durable sandwich of 1.5 layers of 18oz. canvas, thin padding, and an off-white canvas liner for a brighter interior.
The bottom is reinforced with a riveted HDPE (plastic) plate to keep bag from sagging under load.
Though it's designed as a saddle bag, some folks use it as a front bag.