This Wheel Assembly includes 14 blades and the center hub.  
It is designed specifically for a Richard Glässer 
5-tiered pyramid 01374 and Advent House pyramids 09080-
09084.  

It may also fit other brands, including many early 
Expertic - GDR Era pyramids.

14 Blades (Paddles) - RG92019
    13,0 x 4,5 cm (5 x 1-3/4 inches)
Hub - RG91006
    11,0 x 6,3 cm (4-1/4 x 2-1/2 inches)
Diameter Assembled - 36,7 cm (14-1/2 inches)
Hole for metal rod/shaft - 6,0 mm Ø Diameter

Made in Germany by RG
Erzgebirgische Volkskunst 
Richard Glässer GmbH Seiffen