Don't let the cold weather or short days get in the way of your commitment to the sport. Whether its desperately trying to find some form in early February, or even warming up before a race, make this the year you appreciate the focus and improved form that can only come from riding rollers. And if you're in the market, you might as well get some good ones that'll last and built with precision and that's exactly what you get with Kreitler's Alloy 4. 5 Rollers. These drums provide the lowest resistance on offer from Kreitler so you can focus on leg speed and a smooth cadence. You can pair the rollers with the Killer Headwind Fan or the Flywheel if more resistance is required. The rollers measure 15-inch wide and the alloy drums are turned on a CNC lathe from aircraft-grade 6061 alloy to within two-thousandths of an inch concentricity. The drums spin on high-grade ABEC-5 sealed cartridge bearings and this version features alloy endcaps which are heavier than the polycarbonate endcaps found on the Challenger series. The alloy endcaps create more momentum for a more realistic ride and increase durability. The frame folds for easy storage and travel and easily adjust to wheelbases with no tools necessary.