The Ultimate Rotary Engine
This model won't be restocked after April 30 — grab yours while stock lasts
Step by Step Paper ManualThree rotors. No pistons. The engine that rewrote the rules.
The Ultimate Rotary Engine is a large display-scale showcase of the most unconventional engine architecture ever put into production, built from precision pieces and fully motorised. Three exposed rotors spin in perfect harmony through a functioning 4-speed manual gearbox, driven by an electric motor that keeps the mechanism running continuously.
- Three rotating Wankel rotors in full mechanical display
- 4-speed functional manual gearbox
- Electric motor for continuous motorised running
- Large display-format build — over half a meter long
- Fully exposed mechanism visible in operation at every angle
- Parts grouped by section with printed step-by-step instruction manual
Delivered in the 24builds® Collector's Box. Three rotors. No pistons. Built forever.
24builds® offers free tracked & insured worldwide delivery on all orders through premium couriers such as FedEx, UPS, DHL and more.
Orders to EU/EEA, USA, Canada, Australia & New Zealand are all shipped within 5-10 working days.
Please note that in order for us to minimise delivery time and to be able to keep international delivery free, we replace any original boxes of the product with a smaller, more ergonomic and more secure packaging option.
Order cancellations
You’ll be able to cancel your order during the first 24 hours since purchased, and if hasn't entered transit.
Returns
Unopened merchandise may be returned for a full refund within 30 days of receipt of your order.
More info
Please see our Shipping Information page for more detailed shipping times by region.
The ultimate assembly experience
Every detail of our assembly experience is designed for a premium build, making every step as special as the model itself.
Watch Rotary Power in Motion
A Gearbox You Can Follow
Sculpted Mechanics on Display
Model specifications
2178
52cm x 23cm x 29cm
20.5in x 9in x 12in
MouldKing
10214
24builds® Collector's Box
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Educational value
Engineering you can build. Each set breaks down real-world mechanics— from engines to aerodynamics — helping you understand how things truly work.
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