Pocket Mirror
Sends what you hold in your other hand into a Through-Mirror, from anywhere. Right-click a Through-Mirror to make it look into that one, then use it. Or sneak and right-click an Ender Chest: then it opens your Ender Chest from anywhere. Costs the flux of the chunk you stand in. Deepened by Confluence into the Deep Mirror.
kinditemcreative tabFluxion
In the Codex
Entry 
Through-Mirrors — A pair of mirrors that carries things anywhere. Read a portal — to the Nether or to the End.