Though the extant bullet bags vary, it is only slight. This type is frequently seen and very similar to others seen attached to bandoliers around Europe. The colour of the leather alters depending on the type of leather, but like the originals, they are brown in colour and not light tanned like a gentleman’s buff coat. Fingers soon get dirty from black powder and handling lead bullets so the darker colour makes good sense to me. Mine is a copy of the Tower of London ones and it does indeed hold twelve full bore bullets. The draw string action, operated by the touch box, ensures the bullets stay in place even when the bag us turned upside down during priming. All stitching is by hand as is the whole construction process. My wife makes them on our kitchen bench in fact.
Tarred hemp string is provided for fitting to the belt but the draw string also goes around the touch box/primer that hangs below the bag. If you require the touch box, it will need to be ordered separately and comes with string.