ABOUT THE SHOTGUN PRO KIDS MOUNTAIN BIKE SEAT:
Designed for children 2 – 5 years (up to 60lb / 27kg)
Zero frame contact
Adjustable leg length and width to fit electric and regular mountain bikes
Super fast to fit, remove and swap between bikes
Fits all mountain bikes with standard 1 1⁄8 steerers (10mm stem clearance required)
Optional kids handlebar accessory sold separately. 
"With no frame contact (hooray carbon framers!) and the ability to adjust its legs to fit wider frames (hooray ebikes!), the Shotgun Pro is a perfect accessory for an even wider array of mountain bikes than the original Shotgun seat. But perhaps its biggest "upgrade" is the lightning fast mounting process, and the super quick adjustments when swapping from bike to bike". - Two Wheeling Tots