Very correct for an introduction to the macro

Good quality, delivered on time.
Works great on the Canon EOS 70D
No contacts so lost settings, but you can keep opening like this:
Mount your goal without the rings on the case
Aperture Priority, select your value
Press the button to "visualize the depth of field" (Canon on the bottom of the case, under the lens)
Hold down and remove the lens, the diaphragm remains in the selected position when making adjustments.
Assemble your rings and you play.