Our 8mm ammo bands are made-to-order by our very own Wes Mitchell. We use 0.5mm latex (your choice) tapered 20-12mm with an active length of 240mm (9.45”). These bands are meant to shoot 8mm (5/16”) steel ammo; you should trim them to your preferred active length before using them. We recommend using an elongation factor of 1:5-5.5 (500-550%), which will enhance band performance without causing premature failure. For someone with a 30” draw length, that would be 30/5  (6”) or 30/5.5 (5.45”). They would simply trim their band set to ~5.5” or 6” with a sharp pair of scissors or rotary cutter, ensuring that both sides of the band are even. We use 50mm microfiber pouches on these band sets, but the color choice is yours!