17" Balsa LAMINATED Propeller KIT for Rubber Designed for use with large rubber powered aircraft (approx 40" wingspan), this propeller kit is very easy to assemble - just glue the numbered parts together and sand the edges smooth. Being made from balsa, it is vunerable to knocks and chips, particularly on the leading edge. It will not stand a high speed crash into a hard surface at all well ! Please fly with caution. Please note that this is a kit of laser cut wooden laminations for you to glue and sand to shape.