# Determining a weatherproof padlock

**URL:** <https://boards.straightdope.com/t/determining-a-weatherproof-padlock/261286>\
**Category:** Factual Questions\
**Created:** [August 24, 2004, 4:01pm UTC](https://boards.straightdope.com/t/determining-a-weatherproof-padlock/261286 "2004-08-24T16:01:17Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![The\_Controvert](https://avatars.discourse-cdn.com/v4/letter/t/dec6dc/32.png) [@The\_Controvert](https://boards.straightdope.com/u/The_Controvert)\
**Post date:** [August 24, 2004, 4:01pm UTC](https://boards.straightdope.com/t/determining-a-weatherproof-padlock/261286/1 "2004-08-24T16:01:17Z")

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I need a weatherproof padlock for my garden gate. I was given a Masterlock padlock with key by a friend and it has a blue plastic runner along the bottom on an otherwise metallic steel skin. Absent the packaging, how can I tell if this is a weatherproof lock or not? I don’t want it to get rusted shut on my gate.

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**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\
**Post date:** [August 24, 2004, 4:14pm UTC](https://boards.straightdope.com/t/determining-a-weatherproof-padlock/261286/2 "2004-08-24T16:14:51Z")

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Are there any model numbers stamped on it anywhere? Absent that, I don’t see any way, short of a field test, to determine if the lock will rust or not. What you _can_ do is spray it thoroughly with WD-40 every few months. WD-40 is excellent at repelling the moisture that leads to rust (trivia: the WD stands for _Water Displacer_). Use it sparingly; you don’t need to soak it with the stuff–a thin coat is sufficient.

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**Author:** ![gotpasswords](https://avatars.discourse-cdn.com/v4/letter/g/c57346/32.png) [@gotpasswords](https://boards.straightdope.com/u/gotpasswords)\
**Post date:** [August 24, 2004, 4:16pm UTC](https://boards.straightdope.com/t/determining-a-weatherproof-padlock/261286/3 "2004-08-24T16:16:48Z")

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Sounds like a plain ol’ lock there. It’s probably weather resistant, so it won’t turn into a lump of rust after the first heavy fog, but [weatherproof locks](http://www.masterlock.com/cgi-bin/app_search.pl?sub_cat_id=D312D) are pretty obviously so with their full plastic casings. And for about ten bucks, why not just go get one that you know isn’t going to rust shut?