The bars are dome-shaped, which boosts shelf stand-out and offers a point of difference.
At launch they benefited from Alpen's 2002 rejuvenation programme and from its colour-coded packaging. They won support from the brand's sizeable marketing budget, including the nourishment without punishment' TV campaign featuring comedy star Arabella Weir.
In addition there was activity focused on the bars themselves at the time of launch.
The activity seems to have had the desired effect, because the products have performed well, with Information Resources recording sales of more than £10.5m for the range for the year ending May 17, 2003.
A buyer for one of the major multiples said the products' rate of sale had outstripped some of the more established brands. "We took only two of the four variants at first but in a recent range review, we doubled this and expanded distribution," he added.
Trevor Hart, sales director for brand owner Weetabix, said the products had "exceeded all expectations".
He said the brand's latest four-weekly sales figures put it third in the cereal bars sector behind such long-established names as Kellogg's Nutrigrain and Kellogg's Cereal & Milk bars.