This sack truck completely let me down. It is poorly designed and consists of flimsy components.
The wheels are smooth plastic (so no good for rough or uneven ground such as long grass or soil) and the design is such so that they slide around on the axle, giving them a tendency to buckle. It might be ok to move stuff a short distance along concrete, but if you want to transport anything across rough ground, forget it.
The horizontal mode is a complete waste of time. The black mesh surface only attaches to the frame at one end and comes off very easily. Each time you put it back on, you have to bend the bit that attaches to the frame, which means inevitable they will snap. The mechanism for attaching the handle to the frame for horizontal mode is not secure and the handle keeps coming off. The handle itself felt pretty flimsy but in truth it hardly got used because it kept coming off the frame.
The main frame (red part) is sturdy and well built but I found it too narrow for practical purposes, so that, in combination with the poorly designed wheels/chassis, the thing kept tipping over.
In case anybody from the manufacturers reads this, I kept well within the weight limit. All it had on it was a cooler box, a gazebo and a couple of tents.
4 weeks after I bought it, it went to the tip. Not fit for purpose. Complete junk.