SCP-005 - Skeleton Key
SCP-005 seems to have the unique ability to open any and all forms of lock, be they mechanical or digital, with relative ease.
SCP-004 - The 12 Rusty Keys and the Door
Testing on SCP-004 reveals that ten of the keys open SCP-004-1 on a dimension where the laws of physics and topology are significantly different than those of our home dimension.