Source Four Donut for 5° Unit BlackSource Four Donut accessory that reduces flare in template reflection. this can be applied to a 5 degree lens tube. Product Features Source Four Donut accessory Reduces flare in template reflection Can be applied to a 5 degree lens tube To be used with a 5 degree Source Four Black as standard colour Product Specifications Dimensions 19 50 Source Four & Source Four jr X = 3. 25 Y = 6. 25 10 Source Four X = 6 Y = 12 5 Source Four X = 7 Y = 14 X=