Display Block
Display Block · decorative block · Tradery · updated in 1.0.0
Right-click your display block and click its slot with an item. The case shows a copy of it. Your item stays in your hand, nothing is stored inside, and nobody can take anything out. The second button picks the animation: spin, bob, both, standing still, or hidden.

Only the owner opens its screen or breaks it. An admin holding the Vendor Key can do both. Explosions don't destroy it and pistons don't move it.
Crafting
Glass × 5
Any slab × 3
Crafting table.