Vinten 3724-3 Mitchell Spider with Wingnut

The 3724-3 is the spider that mounts a Vector pan and tilt head onto a Mitchell base. It is the standard broadcast interface for hired-in supports and for anything rigged in a house that standardised on Mitchell.

The adaptor supplies as a set: spider, wingnut and key, with the fixing hardware included. The wingnut is what lets a head be dropped in and locked by hand rather than needing a tool at height.