There are a few things to consider when changing a flash suppressor on an AR-15. First, you’ll need to know what type of flash suppressor you have. There are two main types: A2 and A3. The A2 is the older type and has two prongs, while the A3 is newer and has four prongs.
Once you’ve identified the type of flash suppressor you have, you’ll need to find the appropriate tool to remove it. For the A2, a special wrench is needed; for the A3, a regular wrench will work.
Then, use the wrench to remove the old flash suppressor and replace it with the new one. Make sure that it’s tightened securely before using the rifle.
If you’re not comfortable changing the flash suppressor yourself, you can always take it to a gunsmith or gun shop and have them do it for you.