Rare unusual British padlock lock (unusual shackle)

this one does have an odd shackle.

Old padlock with 3 original keys. Shackle has an unusual shape.

Lock is 3" tall x 2" wide.

Heavy brass lock, works perfectly, excellent condition, never used. - eBay (14 April 09)

I have no idea what the purpose of this lock is for.

This padlock had a high bid of $178.50 (Plus $8 Shipping).
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