What is MJI? Motorised Mechanical Animals and Brick Flowers Explained

MJI is a Chinese building-brick brand that makes two kinds of sets: mechanical animals built with real gears that move on their own, and brick-built flowers and plants that never wilt. Their motorised sets come with a motor and battery pack, so a finished shark swishes its tail and lights up at the flick of a switch.

In this guide we explain who MJI are, what their mechanical and botanical sets are like, and why they offer some of the best value in brick building today.

Who are MJI?

MJI is a building-brick brand from China. They may not be a household name yet, but builders who like a good mechanism should know them. MJI focus on two themes that are very different but equally satisfying: mechanical creatures that really move, and brick-built flowers and plants.

Their sets are built from ABS bricks that are compatible with the standard brick system, so spare parts can go straight into your own creations once you are done.

What do MJI make?

Mechanical and motorised sets

This is where MJI shine. Think of a mechanical shark, frog, whale, octopus, dolphin, T-Rex, mantis or sea turtle, built with real gears and linkages. The motorised editions we sell come with a motor and battery pack, so the finished model moves on its own, and many also have built-in lights. Some designs are "semi-mechanical", showing off part of their inner workings.

These are proper builds. The 13054 Mechanical Shark has 687 pieces, the 13058 Semi-Mechanical Frog has 898, the 13059 Mechanical Whale has 1,388, and the 13085 Mechanical Octopus goes all the way up to 1,768. The mechanical sets are recommended for ages 12+, which makes them a great project for teens and adults, or for a parent and child building together.

Botanical sets

MJI also make bouquets, orchids, bonsai, succulents and flower frames. A butterfly orchid, a bird of paradise or a plum blossom bonsai looks lovely on a desk or windowsill, needs no water, and makes a thoughtful gift for someone who would enjoy a calm, mindful build.

Why MJI sets are fun to build

There is something special about building a mechanism and then seeing it work. With MJI's mechanical sets you watch a gearbox come together step by step, and you start to understand how a crank turns into a wing beat or a tail swing. When the motor goes in and the model comes to life, it is a genuine "wow" moment.

They look great on a shelf, and they move too. You can switch them on, show them to friends, and pick up some real engineering ideas along the way. The botanical sets are the opposite in mood: slow, relaxing builds where you shape petals and leaves one by one until a whole bouquet appears.

MJI vs LEGO: how do they compare on price?

We compared three MJI mechanical animals with the most similar LEGO animal sets on sale in the Netherlands, using price per piece and official LEGO.com NL prices (checked 3 October 2026).

At official prices, each MJI set costs roughly half or less per piece: about 50% less for the shark and horse, and about 65% less for the lion. The MJI sets also come with a motor, battery pack and lights, which these LEGO sets don't have. LEGO is often discounted in Dutch shops, though. The lowest prices listed on price comparison site BrickVIP bring the LEGO shark down to 6.5 cents per piece and the horse to 5.2 cents. That narrows the gap, but both still cost more per piece than their MJI equivalents. We couldn't find a listed street price for the newer LEGO lion.

Piece counts are only a rough guide, because part sizes and designs differ, and LEGO makes excellent sets. But if you want a big build that actually moves, at a fair price, MJI is hard to beat.

MJI sets at Toy Haven

We carry around 70 MJI sets, split roughly evenly between mechanical and botanical builds, priced from €7.95 for a mini succulent set up to €49.95 for the largest models. Many MJI sets are sold as pre-orders: you order now and we ship as soon as new stock arrives. The product page always tells you which is which. Some favourites:

• MJI 13054 Mechanical Shark – 687-Piece Motorised Set, €30.00.
• MJI 13058 Semi-Mechanical Frog – 898-Piece Motorised Set, €20.00.
• MJI 13098 Mechanical Pink Dolphin – 888-Piece Motorised Set, €35.00.
• MJI 13087 Mechanical T-Rex – 1,268-Piece Motorised Set, €39.95.
• MJI 13115 Butterfly Orchid – 619-Piece Botanical Set, €19.95.

See the full range in our MJI collection, or jump straight to the MJI mechanical sets or the MJI botanical sets. New to non-LEGO bricks? Our overview of alternative brick systems and our comparison of brick building styles are a good place to start. Pokémon fans should also read our guide to Keeppley Pokémon building sets. Like models that move? Mould King make a remote-control locomotive, and DK make big mechanical-style animal display sets.

Frequently asked questions

Are MJI sets compatible with LEGO?

MJI sets are made from ABS bricks that are compatible with the standard brick system, so spare parts can be combined with bricks from other brands in your own builds.

Do MJI mechanical sets really move?

Yes. The motorised editions we sell include a motor and battery pack, so the finished model moves on its own, and many have built-in lights too. Semi-mechanical designs also show off part of their inner workings.

What age are MJI sets for?

MJI's mechanical sets are recommended for ages 12+. They are a great project for teens and adults, or for a parent and child building together.

How many pieces do MJI mechanical sets have?

Our mechanical sets range from 687 pieces for the 13054 Mechanical Shark to 1,768 pieces for the 13085 Mechanical Octopus.

Where can I buy MJI sets in the Netherlands?

Toy Haven stocks around 70 MJI sets online, with free shipping within the Netherlands on orders from €60. Sets on pre-order are clearly marked on the product page.

Start your first mechanical build

Toy Haven is an online toy shop based in Enschede. We also travel to conventions across Europe, including FACTS in Ghent (31 October – 1 November 2026) and Milan Games Week (27–29 November 2026), where you can collect online pre-orders at our stand. Pick a creature, grab a free evening and shop the MJI collection at Toy Haven.