I have the 50 AMP version and have always been able to pad lock the folding cover on the power post. That secures the surge protector quite well. It sticks below the cover but you can't unplug it with the cover closed and secured.
Bill
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Life is a journey, not a destination.
2005 Georgetown 359ts
Bill & Virginia, Kentucky
Nights camped in 2011...78 , 2012...73,
Nights camped in 2013...123, 2014 ...101