Most Moen shower handles use a 7/64-inch Allen wrench (also called a hex key) to loosen the set screw and remove the handle. This same size typically works whether you’re dealing with a Moen shower handle, a Moen kitchen faucet handle, or another Moen faucet Allen wrench — Moen has kept this hex key size fairly consistent across most of their handle lines. Delta shower handles are slightly different and more commonly use a 3/32-inch Allen wrench, so check your model before buying one.
If you don’t have the right size on hand, a standard hex key set (found at any hardware store) will include both the 7/64-inch and 3/32-inch sizes. Look for the small set screw underneath the handle’s decorative cap — that’s where the Allen wrench goes to loosen the shower handle set screw.
If you’re unsure which wrench you need or run into a handle that won’t budge, the professionals at 5 Star Plumbing are always available to help with any shower or faucet-related issues.