The 104 BCD Carrier Spider enables cost-effective and eco-friendly 4-bolt 104BCD chainring replacements on e-bikes compared to Direct Mount Rings. Made from 6-series alloy, it combines lightness and stiffness and pairs with either durable steel or lightweight alloy rings. Compatible with Bosch Gen4, Fazua Ride 60, Shimano EP8, and TQ HPR50 interfaces.Forged and CNC optimized alloy for stiffness and lightweightAllows use of either affordable, long-wearing steel, or lightweight alloy chainrings.Easily service/replace or adjust chainring size affordably and with less wasteCompatible with all 104BCD chain rings55mm Chainline - available for Bosch Gen 4, TQ HPR50, Fazua Ride60 or SHIMANO EP8 motors