Tribrach

A survey accessory used for leveling that attaches to a tripod. Additional survey instruments or accessories are placed on it and secured with a locking mechanism. it has leveling screws so the whole assembly (survey instrument or prism base) can be leveled correctly. it may also include an optical or laser plummet that allows the assembly to be centered over a survey control point on the ground, and a circular level vial that allows for rough leveling.