A mounting system comprising: • a device case comprising: ∘ an insert: ▪ comprising a rectangular bore; and ▪ defining a set of undercut sections about the rectangular bore; ∘ a first set of magnetic elements arranged in a first pattern about the rectangular bore; and • a mount comprising: ∘ a body; ∘ a polygonal boss: ▪ extending from an inner face of the body; and ▪ configured to insert into the rectangular bore of the device case; ∘ a set of jaws arranged on the polygonal boss configured to transiently mate with the set of undercut sections to constrain the polygonal boss within the rectangular bore; ∘ a second set of magnetic elements: ▪ arranged in a second pattern about the polygonal boss; and ▪ configured to transiently couple to the first set of magnetic elements of the device case (no) to align the polygonal boss with the rectangular bore of the insert of the device case, to transiently retain the mount against a rear face of the device case (no), and to draw the set of jaws toward the set of undercut sections of the insert; and ∘ a locking control configured to trigger a subset of jaws, in the set of jaws, to decouple from a subset of undercut sections, in the set of undercut sections. • a device case comprising: ∘ an insert: ▪ comprising a rectangular bore; and ▪ defining a set of undercut sections about the rectangular bore; ∘ a first set of magnetic elements arranged in a first pattern about the rectangular bore; and ∘ an insert: ▪ comprising a rectangular bore; and ▪ defining a set of undercut sections about the rectangular bore; ▪ comprising a rectangular bore; and ▪ defining a set of undercut sections about the rectangular bore; ∘ a first set of magnetic elements arranged in a first pattern about the rectangular bore; and • a mount comprising: ∘ a body; ∘ a polygonal boss: ▪ extending from an inner face of the body; and ▪ configured to insert into the rectangular bore of the device case; ∘ a set of jaws arranged on the polygonal boss configured to transiently mate with the set of undercut sections to constrain the polygonal boss within the rectangular bore; ∘ a second set of magnetic elements: ▪ arranged in a second pattern about the polygonal boss; and ▪ configured to transiently couple to the first set of magnetic elements of the device case (no) to align the polygonal boss with the rectangular bore of the insert of the device case, to transiently retain the mount against a rear face of the device case (no), and to draw the set of jaws toward the set of undercut sections of the insert; and ∘ a locking control configured to trigger a subset of jaws, in the set of jaws, to decouple from a subset of undercut sections, in the set of undercut sections. ∘ a body; ∘ a polygonal boss: ▪ extending from an inner face of the body; and ▪ configured to insert into the rectangular bore of the device case; ▪ extending from an inner face of the body; and ▪ configured to insert into the rectangular bore of the device case; ∘ a set of jaws arranged on the polygonal boss configured to transiently mate with the set of undercut sections to constrain the polygonal boss within the rectangular bore; ∘ a second set of magnetic elements: ▪ arranged in a second pattern about the polygonal boss; and ▪ configured to transiently couple to the first set of magnetic elements of the device case (no) to align the polygonal boss with the rectangular bore of the insert of the device case, to transiently retain the mount against a rear face of the device case (no), and to draw the set of jaws toward the set of undercut sections of the insert; and ▪ arranged in a second pattern about the polygonal boss; and ▪ configured to transiently couple to the first set of magnetic elements of the device case (no) to align the polygonal boss with the rectangular bore of the insert of the device case, to transiently retain the mount against a rear face of the device case (no), and to draw the set of jaws toward the set of undercut sections of the insert; and ∘ a locking control configured to trigger a subset of jaws, in the set of jaws, to decouple from a subset of undercut sections, in the set of undercut sections.