Heil Sound FL-2 Permanent Flange Mount The FL-2 flange mount allows the Heil PL-2T (sold separately) overhead boom to be permanently mounted to a desk or table top with 3 supplied screws Also has a security lock so the PL-2T can be tightened to the exact position desired The Heil Sound FL-2 flange mount mounts the Heil PL-2T (sold separately) overhead boom to a desk or table top with 3 supplied screws Also has a security lock so the Heil PL-2T can be tightened to the exact position desired