Vello Extension Tube Set for Canon EF Filter Type_Filter Holders It features a sturdy metal

It features a sturdy metal housing with geared focus and diaphragm controls and an internal-focus design that minimizes focus breathing

but you probably shouldn't be taking portraits of people who are running away really fast anyway

No mechanical or electronic coupling: this is a fully manual tube

8 Pan Focus turns your Auto 110 into a fixed-focus point-and-shoot cameras

Vello Extension Tube Set for Canon EF Filter Type_Filter Holders It features a sturdy metalA set of three extension tubes for Canon EF mount: 13mm, 21mm, and 31mm. These tubes have the electronic contacts necessary to maintain autofocus and autoexposure capabilities. If you're curious about dabbling in macro work, this is an inexpensive way to get started.