Autoclaveable Drop Dispensers are used to place sterile stir elements (Discs, bars or dowels) into wells after the liquid is added to the wells. These dispensers can be sterilized by autoclaving or by heating in a hot air oven. These dispensers contain ordered depressions in an top plenum. The depressions are large enough to accommodate just one stir element.
Once the depressions are filled with stir elements a scraping bar is slid over the top of the depressions to remove excess stir elements. The dispenser is then placed over the microplate and the top plenum adjusted so the plenum holes align with holes in a bottom plenum and the stir elements fall into the wells. The bay at the right side of the dispenser can be filled with enough stir elements to fill 4 microplates without reloading, just slide the scraping bar to the left and fill the depressions and repeat. This is a simple and aseptic method of loading liquid filled wells with sterile stirrers.