Entirely 3D-printed (minus nuts and bolts) model of WWII Goliath tank, measuring about 4.5x3x2". BLE enabled and lots of room for expansion.
Goliath tank Black Box Toys - Machinegun
Mini Goliath Tank
Special tanks - Germany (WW II): books
German Goliath, self propelled, cable controlled mini-tank filled with high- potential explosive. Russia June 1942
Tracked demolition charge (Goliath etc.) > WW2 Weapons
Special tanks - Germany (WW II): books
Goliath tracked mine - Wikipedia
Mini Goliath Tank
What is the smallest tank ever built (not mini)? - Quora