... material.Features:1) Model 97-4301: a) Glass dropper 3" straight, 12/pk b) Quality black rubber ... bulb2) Model 97-4302: a) Glass dropper 3" curved, 12/pk b) Quality black rubber ... bulb3) Model 97-4401: a) Glass dropper 4" straight, ... have many other lab glassware, including stain dish, glass stirring rods, desiccator,Petri dish, media storage, ...