A keyless brass lock. This is such a neat lock! Made of brass and marked "Berkmann Mfg. Co. - Chicago - No-Key Trademark. It has 8 "bumps". When the bumps are pressed, the lock will open. We tried it - it works! No turning a dial - no keys. A card with instructions and the code comes with the lock in the original box. - eBay
This amazing and certainly rare example of this lock sold for $277 (Plus $4.80 Shipping).