A hen hackle bag is about 15 x 6 (the ones I have anyway), so that set the parameters for a tying box for me. The Effective Fly Box doesn’t require a whole lot of materials, so organization inside the box wasn’t super important to me. I wanted something I could throw in the car if I were travelling somewhere and something waterproof. Less to keep things dry, more to keep bugs out.
I landed on this Plano dry box. It’s got a seal around the main compartment, a little area on top for tools and to keep a bottle of nail polish isolated. It’s also a neutral color and has space to customize it with stickers. I think an ammo can might work well too. A shoe box wouldn’t be too far off in size, but while the price might be right durability might not.
If stuff goes together (like beads or chenille) I stick them all in a sandwich bag. If something comes in pretty good storage already (like beads) I leave ‘em in the pack. I scrounged up a plastic container for the Sally Hansens so it had a better chance of staying upright and staying contained if it didn’t. I added a storage tube you can buy at your fly shop for spools of thread, wire and non-lead weight.