Finally a battery box that looks as good as an Optima battery performs. Manufactured from 6061T6 aluminum with polished aluminum hold down studs and stainless fasteners. They include 5/16” mounting holes in the bottom (mounting fasteners not included) and fit genuine D34 series Optima Batteries measuring 10"L X 6.8"W X 7.8"H. With a ball milled top and a bright polished finish or in a variety of our Fusioncoat or anodize colors.