Poly Silk Black takes the soft directional quality of a silk and adds the discipline of a dark fabric, taming the light that passes through without splashing bounce back into the room. DPs reach for it over a backlight or anywhere a white silk would lift the ambient level more than the scene can take. LA Rag House sews these in the USA, from the little 4x4 slip-on up to a 20x20 for the big frames. Quietly does its job, which is the whole point.