No, 3M rubber strips attached to the both stand's "legs" & cradle (dock) protect your desk from scratches.
Yes, the stand is compatible with 21" - 27" iMacs and Apple Thunderbolts monitors at Rear insert position; and all monitor up to 32" at top placement position.
We include two high-quality USB 3.0 cables and one 3.5mm audio cable in the stand set; cables are directly connected to your iMac or Thunderbolt USB ports for best capacity.
Yes, the "nesting" area under the stand is wide enough (470mm) to store a full size Apple keyboard with the numeric keyboard.
Yes, the space under the stand is big enough to store a Mac Mini or an any size of Macbook air, Macbook Pro.
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