They sell foam cores with their XLT, but the rest seem to be built up kits.

If you need foam cores for any project, I highly recommend Don Turnock at Eureka Aircraft. www.eurekaaircraft.com

Check out his replacement core options. If you ever need anything, he can custom cut it for you as well- that goes for kitting a model too. Short kits or full kits. He choses great wood.

Don has recently gone to a CNC cutter for his wings. A few years ago there were some inconsistancies, but this machine seems to have fixed that. I highly recommend Eureka.

Brian