Solid Front Wheels for the Razor Ground Force, Ground Force Drifter, & Ground Force Drifter Fury Go-Karts (Set of 2) Pride Lifts Silver Boom 250 Complete as shown P49-1319 Harness:With Knob & Harness the very same wheel MotoTec MT-ATV Mini Quad

Complete as shown

then Monster Scooter parts have what you have been looking for

This Replacement 16" Wheel for the 2018 Sunlite Pet Trailer is an economical solution for a missing or unuseable 2018 Sunlite Pet Trailer wheel

The Forza F-2 features a stable heavy-duty steel frame and a quiet magnetic resistance unit for a riding posture and "feel" you are used to

Of course this means that you can fit it on many other types of backpacks as you desire

Solid Front Wheels for the Razor Ground Force, Ground Force Drifter, & Ground Force Drifter Fury Go Karts (Set of 2) Pride Lifts Silver Boom 250 Complete as shown P49 1319 Harness:With Knob & Harness the very same wheel MotoTec MT ATV Mini Quad Complete as shown then Monster Scooter parts have what you have been looking for