Tell Tails - Shroud mounting - 4 tales - 2 Tales for light wind ( red) and 2 for regular wind. Light design, the nylon washer allow the ribbon to rotate 360 degrees. Nylon ribbon- Easy to mount. Lightweight, ripstop nylon Air-Flow Tails. Works in all shrouds up to 1/4" and 5/16"( change washer , included)