2PCS Robot Car 95cm Crawler Tank Treads Tracks with Gear for Robot Tank DIY Project for Teen Adult(Not Included Idler Wheels)

Nice tracks for excellent price.Fiddly, because it comes in two parts, and for some reason the seller does not provide the pin to connect the two, and to then connect the end. So you'll have to disconnect two elements in order to extract the pins, and then connect the two tracks and form a closed loop. Pins are roughened/thickened on one end, so they hold inside the plastic track. I found at least one pin that did not have this, and the track hence opened spontaneously.But for relatively little money, overall great value and with a pit of fiddling, works fine.

As someone already pointed out, you only get two drive wheels and enough track to make two ~15" tracks. Good quality stuff. You can find this exact same track with idler wheel assemblies on Ebay but you pay $25 for only one track. You can also find complete robot chassis assemblies here on Amazon with a different solution for the idler wheels for about $80. So if you are not the type to devise your own idler wheel solution, you should look elsewhere as I've been unable to find idler wheels sold separately. However, I decided to just use 2" washers with a 1/2 spacer between them as a solution for now.The drive wheels are designed for a 4mm axle and are locked on with a screw. Note that the axle cannot pass completely through the drive wheel as it is held together by a screw into the hub on the side opposite the axle opening. The motor axle can protrude into the drive wheel about 24mm.I would also recommend not using the entire section to build your track so you have some spare links. I'm just using a straightened paperclip for the missing pin for the moment but if you do take out some links, you'll have an extra pin to join the ends together.Will post an update once I get some experience with these as I'm curious how durable they are being hard plastic.

Each section of the track/belt is connected by a metal pin. The instructions state that to adjust the length of the track you can simply push out the pins with something like a paper clip. It took me forever trying to push them out before I just gave up and ended up just breaking off one of the track pieces to where I needed the length of track to be and I found out that the pins are barbed on one side, making them virtually impossible to simply push out like the instructions stated. Everything else worked as intended, it was just the track that was incredibly annoying to deal with. Unless you find some magic way to get the pins out without breaking the track pieces, you’re gonna lose some track lengths. (Also I would advice not to do this above carpet, because if you lose a pin they are like thin nails that you could step on. I even accidentally pushed a pin through the top of my thumb, luckily it wasn’t a big pierce.)

The tracks to not have connecting hinge pins. The internet instructions say to push out one of the existing hinge pins (on each track) with a paper clip and to use it to connect the track. I was unable to do this. I finally ended up ordering some 1 mm hardened stainless steel rod and making my own hinge pins. This worked, but it caused a week schedule delay. Other than this, the tracks were fine.Note to vendor. Throw in two hinge pins.

Great kit. Worked perfect for my tank project. I wish it came with forward idler gears as well, would've gladly paid a bit more for that.

This item can be deceptive. It is easy to think that you are getting the parts for two treads, however, in fact you only have gears to run one tread. For example, if you are making a model tank, the gears fit together to make one side of the tank (two gears, one front and one back). You will need to purchase another whole set to finish both sides. The materials, I must say are quality, though.

To use these tracks you need to find or make two idler wheels. I couldn’t find them anywhere on Amazon. The track makes a loop that is just over 15” axel to axel. The tracks seem like good quality and the drive sprockets are very nice. It’s a shame they don’t include the matching idler wheels that are essential to make these work. Some pre assembled track sets on Amazon use these same tracks and you can see that the idler wheels do exist! I made my own crude idler wheels out of wood using a hole saw. There’s a smaller diameter disc sandwiched in between 2” circles. The tracks are for a solar oven tracker. So far they are working well.

The product is what it shows in the picture but unfortunately it did not work for me for Lego Ev3. I should have looked before ordering.