Package of 50 Cover Plates, diameter 33mm Back Catalog number: 435028 Manufacturer: HYDRO-BIOS Availability: In the manufacturer's stock Price on request - + Recommended 435035 Package of 250 Base Plates, diameter 27.5mm Price on request 438001 Surface Plankton Net acc. to Apstein Price on request 435023 Tubular Plankton Chamber, capacity 25ml Price on request