I use .030 Lexan on my Kellet.It is stiffer than poly but I like it because it gives more stability to the rotor.It's available in the hobby store in the race car section The mfg is Bolink R/C Cars INC an 8 by 10 sheet was $3 I believe they have different thicknesses also I am using this on the hinged part of the Kellet pylon.Not for rotor blade attachment.