PING distance sensors prices

Using Arduino Sensors
1

Hi, I have a short question, I saw on Ebay a lot of distance sensors that look very similar but can cost from 2 to 12 uss, what is the difference??

2

nahuelv:
Hi, I have a short question, I saw on Ebay a lot of distance sensors that look very similar but can cost from 2 to 12 uss, what is the difference??

$10? Is this a trick question?

3

nahuelv:
Hi, I have a short question, I saw on Ebay a lot of distance sensors that look very similar but can cost from 2 to 12 uss, what is the difference??

You should probably give more details.
I searched ebay and found the HC-SR04 to be very cheap. I was very surprised. They aren't available yet in my country.