The intermediate friendly 75 IS is similar to the RTM 77, but instead of a full wood core, it gets Volkl's Dual Wood Core construction, in which side-by-side tip-to-tail wood stringers are embedded in lighter weight (and cost-saving) foam. The result is more forgiving performance, which is further enhanced by Volkl's Progressive Technology, where the tail of the ski is thinner and more flexible for easier skidding and less-aggressive turn finishes that won't throw an intermediate off balance rearward. It's part of the seven-model RTM ("Ride the Mountain") series of frontside, all-conditions skis - the all-mountain heart of the Volkl collection. Waist widths range from 84 mm down to 73 mm, with performance and price decreasing along with width. Higher end models (the 84, 81, 80 and 77) are subtly rockered from tip to tail for soft-snow performance. Lower end models (75 IS, 75, and 73) get tip and tail rocker for easy pivoting and skidding and are generally more forgiving and groomer oriented. The RTM collection features Volkl's XTD constructions, which are built with extra mass stacked over the edges for extra stability and edge bite. In lower end RTM models, these XTD rails decrease in size and mass to give those skis more forgiving performance. All but the value-priced RTM 73 have wood cores. All are sold with bindings.