The rear suspension style and design utilizes a conventional mountain bike shock. The AZUB Ti-Fly folds and comes in variations with a twenty” (406mm) or 26” (559mm) rear wheel. The 26” Variation includes a large rear hub plus a thick through-axle to almost remove the wheel flex that some trikers https://tgvstore.com/product/ink-black-mini-trike-platinum-edition-lead-time-applies/