Mounting straps to mount Anker 40W 5-Port USB Charger (power block) to wall / shelf / desktop surface. Use 2 of these clamps, one at front and one at back of device to mount it to your surface. This is designed for #6 wood screws, or "expando jack" screws if mounting in drywall. There are 2 versions available, one with screw holes appropriate for flat-head screws, one with screw holes appropriate for round-head or pan-head screws.
The Anker charger is available on Amazon at https://www.amazon.com/Anker-Charger-PowerPort-Multi-Port-Samsung/dp/B00VH958F0/
Also available are mounting straps for a Amazon Basics 6-Port Power Charger, at https://www.thingiverse.com/thing:2825381