This leather earmuff/headphone shaped thing with straps, Devon, UK

What are these 4 tall masts at a marina in Quebec City? The structure behind it is a grain silo if that adds any context

Found under a hotel bed unsure if left by previous guest or staff. Thin with metal like objects on the edge which rattle when shaken, WITT?

As long as my index finger. Metal part at bottom moves in and out. Not spring loaded.

Yellow plastic piece. Around 9 inches long. Very lightweight. Has a 20 engraved into it.

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What are these small, plastic pieces?

They were found right outside our side door, a couple weeks apart. Pen for scale

Calico Peak rd, High Rolls, NM [OC] [4032×1816]

Mt of the Holy Cross, Colorado (2000x300 oc

Tre Cime di Lavaredo [OC] [2000x781]

Svartisvatnet (Black Ice Lake), Norway (8192x6144) [OC]

[OC] First Day of Fall in the Eastern Sierra Nevada, CA [4025x2315]