Some assembly required, tractor not included
Here it is in action
I heard about this from some local farmers although there is definitely disagreement on what works best.
I use 4 foot fencing so a 5 foot 2x4 works best to give that extra room on the top and bottom for your chain.
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A better and probably safer version is 2, 2x4s bolted together with your fence sandwiched in between and my other buddy said the 2x4s don't work for him so he uses stop sign poles
