Insulators as follows -- Actual postage additional:

U-2421 incuse marked CP 75 in a nice blue-gray -- $4

U-313 cobalt blue -- dome incuse ILLINOIS map - -small dome bruise affects some of the map -- tough style! $8

U-280 no markings -- great mottled blue shade! VNM -- $6

U-292A Recess embossed OB logo - great mottled dark blue -- VNM -- $8 (SOLD)

U-297 inkstamp CHANCE -- great mottled light blue -- few tiny pecks -- $6

Take the remaining four for $20 plus actual postage