Mars has unveiled its latest female-friendly chocolate bar. Twix Fino the first permanent ­extension in Twix's 40-year ­history is being pitched against Nestlé's Kit Kat Senses and Ferrero's Kinder Bueno.

The new countline (rsp: 52p) features a wafer rather than biscuit base and contains 94 calories compared with 142 calories in a standard bar. It joins Galaxy Bubbles, which came out in January, and Mars Delight, launched in 2004, in Mars' growing portfolio of light brand extensions.

Rolling into ­indies and impulse outlets now, followed by the multiples next year, it is aimed at the same audience as the £30m two-year-old Kit Kat Senses. Following three years of "consecutive brand growth", now was the perfect time to extend Twix, Mars said, billing Fino as its biggest launch this year.

"The £90m Twix bar is the number four chocolate bar in the impulse sector and the lighter version will help expand the appeal of the brand to female professionals looking for a lighter snack," said Bep Sandhu, trade relations manager.

She refused to be drawn on whether any further Twix extensions were planned but said she did not rule out other wafer-based variants of popular Mars brands. "We'll always explore formats to meet consumer needs. Wafer-based products perform well in the market."

Mars is supporting the Fino launch with a £2m ATL marketing push next month. It will also roll out its reduced satfat Mars, Snickers, Milky Way, Topic and Flyte bars, as revealed by The Grocer in January. A lower satfat Twix would be launched "in due course", said Sandhu.