Aegis Shield 30" x 30" Main Drain Cover Only (Hardware Included) VGBA Compliant 10-Year Warranty Wall flow: 1120 GPM Floor flow: 1432 GPM This cover easily installs over existing main drain and the only solid fiberglass VGB drain cover available. Requires no grounding to the pool shell and is completely resistant to corrosion. 30" x 30" grate size allows main drain up to 24" x 24" to be covered. Aegis VGB cover includes stainless steel mounting hardware.