2-3 Weeks. The 8200 Series Field-Corps Bass Drums feature an aluminum arch lug casing which is 20 percent lighter and 40 percent stronger than previous models and which uses straight-line technology. The drums are one to two pounds lighter than previous models. 10-ply Birch hoops with a round edge allow pinpoint tension on the hoop, and a new steel wide body caw is designed for today's corps-style tuning, dispersing tension over a larger surface area for more stability. The bass drums also feature a 5.4 mm steel tension rod to provide easy, consistent tuning without unnecessary weight.