Yale Duplex antique padlock

This is a real interesting lock with multiple keys:

Very rare brass lock, 2 original keys. One change key and one master key. Change key and shackle are both marked "B20". The lock works perfect, excellent condition. Lock is 2 7/8" tall x 2" wide x 3/4". - eBay

This lock sold for $362.99 (Plus $5 shipping)

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