BM70 Underwater Thruster: A Lightweight Choice for Small ROVs and RC Boats

If you are building a small ROV, RC boat, or DIY underwater robot and don't want to use a large thruster, the APISQUEEN BM70 can be a simple and practical option.

The BM70 is a 7.4V, 28W brushed underwater thruster weighing only about 86g. Its compact and lightweight design makes it suitable for small underwater equipment.

What Projects Is the BM70 Suitable For?

The BM70 is mainly designed for small underwater equipment and DIY projects.

It can be used for:

• Small ROVs

• DIY underwater robots

• RC boats

• Toy boats

• Underwater experimental projects

For equipment where both size and weight are limited, the BM70 adds very little extra weight to the overall system.

7.4V / 28W for Small Power Systems

The BM70 operates at 7.4V with a power rating of 28W, making it suitable for use with a 2S LiPo battery.

For small ROVs and RC boats, this low-voltage, low-power configuration makes it relatively easy to build a simple propulsion system.

IP68 Waterproof and Suitable for Freshwater and Seawater

The BM70 features IP68 waterproof protection and can be used in both freshwater and seawater environments.

If the thruster is used in seawater, we recommend rinsing it with fresh water after use to reduce salt residue.

36mm Nylon Propeller

The BM70 comes with a 36mm nylon propeller and is available in both CW and CCW rotation directions.

For a single-thruster setup, you can choose the appropriate rotation direction based on the installation.

For a dual-thruster ROV, different rotation directions can also be selected according to the overall design.

The BM70 also uses a coupling connection, making propeller replacement more convenient.

Simple Brushed Motor Design

The BM70 uses a brushed motor with a relatively simple design, making it suitable for DIY projects.

If you are building a small ROV, RC boat, or underwater robot for the first time, you don't necessarily need to start with a large and complicated propulsion system. A lightweight thruster like the BM70 can be enough for many basic projects.

BM70 Specifications

Specification	BM70
Motor Type	Brushed Motor
Operating Voltage	7.4V
Power	28W
Waterproof Rating	IP68
Propeller Diameter	36mm
Propeller Material	Nylon
Rotation Direction	CW / CCW
Weight	Approx. 86g
Water Environment	Freshwater / Seawater
Propeller Connection	Coupling

The specifications above are based on the APISQUEEN BM70 product page.

Why Choose the BM70?

If you need a small, lightweight underwater thruster designed for 7.4V operation, the BM70 is a good option to consider.

It is not designed for large unmanned vessels or high-power underwater equipment. Instead, it is better suited for small ROVs, RC boats, toy boats, and DIY underwater projects.

For projects where size and weight are important, the 86g weight, 28W power rating, and IP68 waterproof design make the BM70 a practical choice.

Final Thoughts

When building a small underwater vehicle, you don't always need a large thruster.

If your project is compact and you are looking for a simple low-voltage underwater propulsion solution, the BM70 is worth considering.

With 7.4V operation, 28W power, an 86g lightweight design, IP68 waterproof protection, and CW/CCW propeller options, the BM70 is well suited for small ROVs, RC boats, and DIY underwater robots.