An apparatus for retaining a photovoltaic panel on a rooftop includes a vessel having a first side, second side, front, bottom, and top panels, wherein the panels are attached to define a void within the vessel. A fill port is disposed on the vessel. A first hole is adapted to receive a screw on the top panel, wherein the first hole is aligned with a second hole disposed on the bottom panel, wherein the first and second holes are adapted to be aligned with a third hole on a first mounting cross arm. The top panel is inclined at an angle relative to the bottom panel.