STEM LAB Arithmetic Model Kit: Mechanical Multiplier & Addiator
Construction Toys - National Museum Of Mathematics
Addiator size: 8.5*4.3*0.91 in (21.5*11*2.3 cm) Multiplier size: 9.8*10*1.6 in (24.8*25.5*4 cm) Package size: 8.07*7.4*2.48 in (20.5*18.8*6.3 cm)
Arithmetic kit 2-in-1 educational mechanical model kit