THIS IS DESIGNED FOR USE WITH THE DURST NEGA 138 / NEGAROLL 70 / MAVET 138 NEGATIVE CARRIERS WHICH ARE USED WITH THE DURST LABORATOR 138S ENLARGER. DURST GLAS PLAIN GLASS INSERT. IT IS A PLAIN GLASS INSERT (NOT ANTI-NEWTON) THAT CAN BE FITTED INTO EITHER THE UPPER OR LOWER SECTION OF THE NEGATIVE CARRIER.
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