Bonus Deeluxe TFP liner included with purchase! When we received these spark boots from Spark, we noticed a small issue with the liners. A manufacturing defect had allowed the leather on the liners to delaminate from the foam. While this defect was very minor and virtually undetectable after a heat mold we felt that the product did not meet Bentgate's standards. Since we're psyched on these boots we did the only reasonable thing. We got new liners of course! The liners are designed for the Spark XV but work perfectly for the Summit. Because of the liner swap, we're offering this boot at an awesome price. With a leather shell and lining, these boots offer premium performance and decadent luxury. Paired with the Boa system, their C3 lacing provides the perfect fit and all day dependability. a New TFP liner features a SympatexAR membrane and leather lining to regulate moisture and maximize comfort. a C3 BoaAR performance lacing offers incredible support and an especially responsive ride. a VibramAR sole and backwelt are perfect for riding, hiking, skinning, or rocking crampons.