This Durst HOMASK, is made out of steel, NOT ALUMINUM!  That is key to negative flatness. 

Durst HOMASK 138/5x7" m negative homask. durst horizontal enlarger speed mask. Make the sharpest possible prints from your horizontal durst enlarger by only going through 1 one piece of clear glass. Lool ma, NO AN GLASS and sharp as can be  prints. 

Very Good to Excellent cosmetic condition 8 out of 10. Function is 10 of 10! Perfectly straight. Zoom Zoom Zoom into photo details please. 

I will also be listing the 35mm Homask as well as others, like the 205 HOMASK , 205 (8X10) 138 (5X7). check my other listings in 24 hours.. See other listings. 

The outside dims are 1.0.25"X10.25".

This fits the Durst speed carrier and may also fit other durst negative carriers. Measure yours before purchasing. 

Sincerely,

Jay  Overmoen

Cedar City,  USA.