Preheat your grill to medium-high heat.
Rinse the clams under cold water to remove any sand or grit. Discard any clams that are open and do not close when tapped.
In a small bowl, combine the melted butter, minced garlic, chopped parsley, lemon juice, red pepper flakes (if using), and a pinch of salt and pepper.
Place the clams on the grill, cup side down. Grill for about 5-7 minutes, or until the clams start to open.
Carefully spoon the garlic butter mixture over the clams as they grill, allowing the butter to melt and infuse the clams with flavor.
Once the clams are fully opened, remove them from the grill and discard any that remain closed.
Serve the grilled clams hot with lemon wedges on the side.