OCTOBER MOUNTAIN SEKTOR ILF RECURVE RISER 17 IN. LH The Sektor ILF Riser is carved from a premium blend of zebrawood and phenolic composite that is 3/64" cut past center, with a crowned arrow shelf at 17" in length. The Sektor ILF riser provides the broadest range of customization and tune-ability with its compatibility of vast ILF limb assortments, lateral limb alignment and tiller adjustability.