This is a pack of two optional K&B Dream Designs HP Extreme Edition 40mm Tail Blades, and are intended for use with 200-250 size helicopters. K&B Dream Designs Helicopter tail blades are created using a complex combination of materials which provide the perfect mix of strength and flexibility. The blades have a very large surface area, yet weigh very little. The colorant is made to strict specifications and is mixed as the blade is created. The color completely permeates the blade, and is not painted or applied. All similarly sized blades are the same weight, allowing the user to customize their tail rotor colors as desired.