Piggy Back Compatibility September 4, 2017 Steven Abramowitz Innovations, Micro Pack, Powder Trekker, Thermal Trekker Carry them both with ease. The Micro Pack conveniently connects and Piggybacks on to KULKEA’s Trekker series bags via the helmet sling clips. (Thermal Trekker, Boot Trekker, Powder Trekker). More Stories TPU Bag Protection Not Just on the Bottom. Kulkea uses generous amounts of high quality tarpaulin on the bottom… Shaped Boot Pockets High & Wide. Kulkea ski boot bags include boot storage areas designed specifically to accommodate the… Isolated Compression No zipper interference. Low profile, always-engaged compression straps for size adjustment and additional load control.