Plastic Base for Outdoor Airconditioner Unit Installation AC Plastic Base. Fillable weight-compartment design, fill with sand or gravel for heavy-duty stability on lawn, soil and soft ground. Reinforced triangle rib structure, high load-bearing capacity, anti-deformation. UV-resistant injection-molded plastic, weather-proof for long-term outdoor use, no rust. Pre-slotted mounting holes, compatible with most AC outdoor units, easy installation. Light-weight empty base, reduce ocean freight cost; add local sand for weight on-site. Perfect solution for garden, lawn, backyard soft ground installation.