10x HY-SRF05 / HC-SR05 Precise Ultrasonic Range Sensor Module for Arduino

Good quality for the price. 8/10 worked on preliminary testing. One thing that I've learned from buying things like this for Arduino/Rasperry Pi is that it's best to order a few more than you actually need. If it doesn't work, these things are so cheap that it's usually not worth the price to send it back for a refund. Plus you've lost a lot of time since these things usually come from China and take a few weeks to arrive. So if you can find a cheaper product expecting to toss a couple of them, it's better than taking the chance from a pricier seller.