Know Your Lawn Mower: When your mower isn't doing the job, diagnosing and fixing the problem (or telling the mechanic what's wrong) is easy when you know what to look for! Thomas Baker, This Old House Magazine
Appears to be made of push lawn mower wheels and axel surrounded by a configuration of PVC pipes and elbows. Covered in foam; that looks like a dollar store pool noodle. Add a web strap band to hold kayak to the cart.
Great States 204-14 14-Inch Deluxe Hand Reel Push Lawn Mower