We bought this one wheel trailer on Amazon
https://www.amazon.com/gp/product/B00BQOMJ9O/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 We have mostly only used it to go out to the mail boxes and UPS drop box which is 1 1/2 miles from our house.
I really like the way it tows, it's a lot better than our old two wheel instep trailer the instep rattles and bounces this one is much quieter. I also like how it tracks right behind you and isn't any wider than your bicycle is. I have a rubber maid tub that fits in the trailer frame which works better than the duffle bag that it comes with. It says it's rated for 70lbs but I don't think I would want to put more than 50lbs on it. I also like how the trailer kick stand holds the bike up which is great for loading the trailer and bike.
I got an extra quick realease axle for it
https://www.amazon.com/Maya-Cycle-Q...99-8126-c95a8bb37121&pd_rd_i=B00BQOS3YO&psc=1
I like this axle better than the one that came with the trailer. This one you can remove the wingnuts and metal plates and washers, the original they don't come off unless you pull the skewer and they jangle and rattle when the trailer isn't on the bike. I just take them off and keep them in my bicycle tool/patch kit when not towing the trailer.
Only small problem they put the flag on the wrong side, it should be on the left since we ride on the right side of the road here, but small complaint over all. I plan to make a bracket to hold the flag behind the reflector.
