I have a penny red queen victoria with letters k and p in all corners--value ?

by JAMES MERRILL
(kansas city, mo usa)

I have look and looked for info these letters on numerous penny red "Q.V" stamps and I have not found any info on them. I only have one . The letters are K in top left and rt bottom. The letter P is in left bottom and top right. slight indifference in perferations on rt side and bottom.

I can not down load pictures at this time but will try if feel the stamp is rare are of some value other then face of "one penny"!