Nothing special...just a 4" PVC longbow tube

[LBR]

Whatever you use for the outside, be sure you wrap and pad the bow inside.  I use carpet "cobs" (the heavy cardboard center of a roll) and boxes, shipped to Hungary,Australia, Italy,Spain, Austria, Romania, and lots of other places,...never had a bow damaged.  Newspaper is a cheap and effective padding.

[Double Tee]

I lucked out last year on the Cabela's web site! They had 6foot fishin rod tubes on sale for $5.00! the shipping was more than the tube but I got one and it works for my 2 Martin Savannahs. They said they were 4" tubes but when I got it, turned out to be 3" but it still works though a bit of a tite fit with the sock over the bow,However the bow doesn't rattle around in the tube!