Fill a stock pot about a quarter full with water and bring to a boil. Add Old Bay seasoning, salt, vegetable oil, and beer.
Add crab legs and return to a boil. Steam for 5 minutes.
Make your sauce by melting butter in a bowl, then add garlic salt, lemon juice, and salt.
Remove crab and set aside. Add corn in same pot and bring to a boil. Remove and serve with the butter sauce. Enjoy!