Sheet metal, die pressed with a built in boss head and spring loaded jaws wrapped in a rubber sleeve for holding burettes vertically in a retort stand. This is made of sheet metal, is die pressed, has a built in boss head, and has spring loaded jaws coated in a rubber sleeve. It is used to hold burettes vertically in a retort stand. A six pack of this item is available. Additionally, we accept large orders at pricing that is comparable with the market.