Use this economical device to accurately replicate colonies grown on 90- to 100-mm petri dishes. A locking aluminum ring (102 mm dia) secures a sterile velveteen square onto a PVC cylinder for easy control of the contact surface.

To replicate colonies, invert master petri dish over device to transfer colony pattern to fabric, remove, and lower device onto fresh agar plate. Disinfect between uses with a brief rinse in ethanol or chlorine bleach. Cylinder is 55 mm H with 80-mm and 88-mm dia ends.