You can keep the mini OBD diagnostic tool on the OBD socket and there is no need to pull it out when itis not used. OBD diagnostic tool with switch is able to enhance this feature.
The benefit of the switch of OBD diagnostic tools is:
1, To help you to save fuel.
2, To avoid interference between communication equipments.
There is a button with the OBD diagnostic tools and you can stopthe OBD diagnostic tools when it is not necessary.