M-LOK and KeyMod are both mounting systems used to attach accessories to firearms and tripods. M-LOK (Modular Lock) uses rectangular slots and is known for its strong, direct attachment and ease of use. KeyMod, with its keyhole-shaped slots, also provides a modular setup but is less widely adopted today. FatBoy Tripods accessories primarily use the M-LOK system for its durability and widespread compatibility, allowing you to attach your accessories securely and confidently.