GoolRC Mini RC Submarine, LSRC-SMI Remote Control Boat Waterproof Diving Toy (Blue)

First, I need to say READ THE INSTRUCTIONS! Particularly about swishing the tail end around in the water before using them. The subs use tiny little thrusters in housings that are small enough to trap air in rendering them useless, hense the swishing part to get the air out. Despite the tiny size of the thrusters, they're surprisingly responsive. Just remember that these are subs, not speed boats. I was surprised that these use actual, proportional ballast to control their bouyency (surfacing and diving mechanic) instead of a thruster like most others, this allows you to surface or dive in place and also trim the sub to stay at a desired depth. All in all these are amazingly fun especially for the price. They're small enough for tub fun but maneuverable enough for pools and small ponds as long as the water is clear. They also use an auto surface feature if they don't get any input or lose signal for more than 10 seconds which is a life saver. Highly recommend!

Very small

This little 6" sub works as advertised. Generally, it stays submerged for a minute, maybe longer, if it is traveling forward. If it submerges and is stationary; it will surface automatically in about 20 seconds. It is fast, and has a green LED light when on. It must be in the water to activate.

This works, but it’s a bear to “drive.” Despite experience with rc gear from high end trucks to airplanes and drones, this thing is hard to manipulate. It’s overly sensitive and finding bouyancy is a nightmare. Steering is slow and cumbersome. While it does basically do what it’s supposed to do, it was a five minute novelty for everyone in my family, from 12-47 years. It’s not worth the money whatsoever, in our collective option.

works like a charm the only thing is charging is a bit difficult if the submarine doesn't work just make sure it's charged and the batteries are working.

It worked for about 3 minutes after the initial charge. Now it won’t charge at all.

Great fun for 6 year old grandson. Had to buy one for myself! You can hear the ballast blow before submerging. For a large amount of water like a swimming pool, stick the tip of the antenna in the water to carry the signal. Very maneuverable.

Great toy for kids. Works under water, easy to charge, great bath toy and for the cost it's awesome 👌