What is the Diameter of the Lock Hole on the Demco Gooseneck Coupler Lock - 30K?
Updated 03/04/2026 | Published 01/30/2026
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Question:
What is the diameter of the lock hole, or what size lock shackles will fit this device?
asked by: Shawn
Expert Reply:
Hello Shawn,
That is a really great question. I always consider it a great question when I cannot find the information anywhere on the internet. I also enjoy a good excuse to stretch my legs, so I grabbed my tape measure and took a stroll out to the warehouse.
The lock hole on the Demco Gooseneck Coupler Lock # DM88KV is exactly 9/16". I attached an image for reference.
The Master Lock Laminated Steel Padlock # ML312KA would work great with this coupler.
What kind of gooseneck trailer are you trying to keep safe?
(click to enlarge)
Product Page this Question was Asked From
Demco Gooseneck Coupler Lock - 30K
- Gooseneck Trailer Locks
- Gooseneck Base Lock
- Demco Couplers
- Steel
- Demco
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Kate F.
3/4/2026
Hey Shawn, did the Master Lock padlock end up fitting well with your Demco gooseneck coupler lock? Knowing how that combo worked could help others looking to secure their trailers the same way.