The haversack is an important piece of kit for any solider. It is what he lived out of for most of the campaigning season. After doing some research I would like to offer the following that might be useful in customizing your haversack. The US Pattern Tarred Haversack [12½” x 3½” x 13” with a 5” flap] had a single strap, an inside cotton sack buttoned at two ends and on one side [the sack is what the food was carried in]. Officially [as per the 1863 regulations] the flap was marked with the company letter and the regimental number, the number of the solider in black [or white] 1½” tall block letters. This was seldom actually seen in volunteer units. As with canteens they could be embellished as per the choice of the individual soldier. The strap was typically longer than required in service. The haversack should be kept at waist belt level to avoid banging against your leg when walking or running. Items kept in the haversack were three days rations [27 pieces of hardtack, 1 lb. of pork, peanuts and beef jerky as well as coffee, sugar and salt]. Other personal items were plate, knife/fork/spoon, cup which is hung on flap outside, writing set, jack knife, neckerchief, cards, pipe/tobacco/cigars, comb, toothbrush, wallet and 40 rounds of ammo.