Oh my goodness, it’s so much better than petroleum jelly (and it won’t degrade latex/rubber). Put it anywhere, you can even eat it, it’s safe for nursing babies.
Other than nipples, it has thousands of uses. I use it under my nose where my CPAP machine rubs me raw. Oh, and it’s a great moustache wax too!
Just try it. I costs a bit more than PJ, but it’s like owning the best quality product of it’s type. Nobody can buy anything better.
For what it’s worth, lanolin is not vegan, despite the pictured ad claiming it’s ethically sourced and implying that animals are not harmed. Lanolin is produced from wool, and if you care about such things, often a result of unpleasant (to say the least) farming conditions for sheep. Probably there are some sources that aren’t so bad, but apparently there are reports that wool industry practices are pretty horrific to the sheep. (Read more here and here if you like.)
On the positive side though, there are plant-based lanolin alternatives, including vegan nipple creams. I couldn’t find any source that weren’t also ads for a product, so I’ll leave the search up to whoever is interested in them.