It's an unbalanced count. Basically, it's a deeper look at the red7 (and credit is given to Snyder for the idea).
The book (Blackjack Bluebook II) I found to be very easy to read. Yes, some of it was simple, and I know a lot of advanced players breezed through it, but as for myself (and a number of others here) it cleared up a LOT.
I had started on red7 because i had first read snyder's Blackbelt in Blackjack. BB II just fleshed it out.
Oh, the BIG difference is red7-count red 7's, where KISS has the black 2's counted. (black 2's, all 3,4,5 & 6 =+1, 10 & a -1).
Hope it helps, and sorry 'bout the 'bot' crack!
(Ohhh, sorry about THAT one, too!)
-EPS