Add-On Bike Rack Extension for 4187 E-Bike Rack, 100 LBS Capacity for 2 Bikes, Fits 5" Fat Tire, Steel-Aluminum Build — NOT a Standalone Rack, Frame Extension Only

EXPANDS YOUR 4187 RACK BY 2 BIKES: Designed exclusively as an add-on for the 10104187 main rack, this extension lets you carry up to 2 additional bikes. Total add-on capacity is 100 lbs. Perfect for family trips, group rides, and longer outings when one rack isn't enough. 100 LBS CAPACITY BIKES ONLY: Carries 2 standard bicycles within a 100 lb total limit. Not rated for e-bikes, heavy-duty bikes, motorcycles, or cargo bikes — for those, use the main 4187 platform. 3" FAT TIRE COMPATIBLE: Wheel cradles accommodate tires up to 3" wide, matching the fit profile of the base module so your full setup stays consistent. UPGRADED ANTI-WOBBLE & ANTI-SCRATCH: Reinforced bolt connections and shock-absorbing threads eliminate sway between the main rack and the extension. Soft padding, rubber covers, and premium tie-down straps keep every bike scratch-free. PREMIUM STEEL-ALUMINUM BUILD: High-strength aluminum and steel frame with professional anti-rust coating. Tested against salt, rain, snow, and extreme weather — built to match the durability of your base module. HASSLE-FREE SETUP: Ships with complete mounting hardware and step-by-step instructions. Snaps onto your existing base module in minutes. DEPENDABLE SUPPORT: Backed by 1-year warranty, spare parts coverage, and responsive aftersales team. Need the base module first? Find it under our E-Bike Racks collection.