An interesting Blast! Deflector back story from YORF:
The MPC starter kit pictured earlier featured a unique parabolic blast deflector. The design made its first appearance as an R&D entry at NARAM 11 submitted by Sven Englund of New Canaan, CT.
This was the very same Sven Englund who was the winner of the Estes "Launch Pad Sweepstakes" which had a trip to see the Apollo 11 launch with Vern Estes as its grand prize. Methinks that ol' Sven might have been the object of envy by a few thousand rocketeers over that win!
Only a few months later the April 7, 1970 issue of Model Rocketry magazine would report that MPC had purchased the rights to his deflector design from Sven for the princely sum of $75 dollars. Here's the story from Ninfinger.org: Model Rocketry Magazine April, 1970 (http://www.ninfinger.org/rockets/ModelRocketry/Model_Rocketry_v02n07_04-70.pdf)
The design is still available today from various model rocketry dealers. (an Odd'l Rockets product!)