Rosco Gobos are round to allow for rotation in the gate when aligning the projected image. The standard "B" size is suitable for most fixtures with a 6" lens when used with a Rosco Pattern Holder or the holders of other manufacturers. Trimming of patterns, where necessary, can be easily accomplished with a pair of scissors.
To insure design integrity the patterns are etched using a precise double-sided process on stainless steel. The result is durable, high quality patterns which will withstand the extreme heat at the gate of ellipsoidal spotlights.