Wimberley alt-az tripod head. Exceptionally well built. For additional information and photos of this heavy duty tripod head see the review on Cloudy Nights, or visit the Wimberley web site (do a Google search for "Wimberley"). Wimberley sells them new for $465 plus shipping. This one is up for sale for $340 postage paid in the USA. Excellent condition. They don't wear out, they don't break. This is the Wimberly head only, no tripod included, just as sold by Wimberley. Fits all standard tripods.