The mark consists of horizontal positioned upper case letters Q, P and R in stylized font with the letter Q in the left most position, the letter P in the middle position and the letter R in the right most position, each of the letters in stylized font featuring in the case of letter Q a thick dark vertical portion of the circular part of the letter emanating from above the letter's lower boundary and following the letter's left curved portion vertically upward and terminating slightly above the left upper curvature of the letter, said letter's lower, non-curved portion comprising a similar thick dark portion of the substantially straight portion of the letter, the letters P and R having their substantially straight portions also similarly comprised of a thick dark feature, said thick dark features of all three letters being nearly identical in appearance.