Comet RS-520 Mobile Antenna Adjustable Lip Mounts Comet RS-520 mobile antenna adjustable lip mounts offer quick, easy installation and removal. These light-duty models feature 3 adjustment planes for up to a 45 in. antenna, fit a 1/4 in. thick or less edge, and adjust to vertical from virtually any angle. Mount your antenna the easy way with Comet RS-520 mobile lip mounts.