Ender 3 and CR10 SD Card Holder
Free     Myminifactory     CGO3D

Ender 3 and CR10 SD Card Holder

Easy simple first modupgrade can be tricky depending on where you mount it  Needs a spare M58 bolt and Tnut to attach it to the frame PS sorry for the bad pictures ...

similar models —

Ender 3 and CR10 SD Card Holder alternatives
SD Card Holder
muddymaker