Acratech Leveling Base, Fits All Standard 3/8-16 Tripod Heads

The Acratech Leveling Base fits all standard tripod heads and connects via a 1/4-20 or 3/8-16 fitting. It is a well-built leveler and works well in very cold conditions as long as it is kept dry. The diameter of the upper mounting surface is about 2-3/8" with the spirit level bump-out at about 3-3/8". Users rave about its build quality, usability, and lightness (8 oz / 240g). The bubble level is easy to see even when a ball head is installed. It's highly recommended for panoramic photography work since the level indicator is off to the side of the head, allowing for better reading of a leveling head. It works perfectly with Acratech GV2 ballheads and the Pano Head. Users love that it's much smaller than a bowl on a tripod. However, one user found it hard to tighten with the short grub screw since the base is hollowed out.