I have previously purchased a Kensington combo lock for my Latitude 5501 and it did not fit. It was also listed as compatible so I tried it out and it fits the hole and locks. This is a one key lock, not a combination, so be careful where you put the key. One thing that impressed me is how small the lock head is. I'm used to big, awkward things dangling from the side of my laptop, but that's not the case here.
RUBAN Notebook Lock and Security Cable: Protect Your PC/Laptop with Two Keys and 6.2 Feet of Cable (Black)
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Enhanced Kensington Cable Lock for HP Laptops, Lenovo, Asus, Acer & Other Devices - Compact & Reinforced Pivoting Lock Head (K65035AM)
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Enhance Laptop & Notebook Security with Sendt Pink Combination Lock Cable
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Secure Your Laptop with the Kensington Portable Laptop Combination Cable Lock - Letter Combination Lock (K64684US)
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