26 year-old defender Ben Chorley joins Orient from Tranmere Rovers.
He has signed a two year deal with the Brisbane Road outfit.
Chorley began his career at Premier League Arsenal.
He played 89 times for Rovers over two seasons, and 139 times for MK Dons after he joined them as Wimbeldon.
"Delighted" Orient boss Geraint Williams triumphed in a battle for his signature.
"He was an integral part of Tranmere's successful defence last year and he was in demand from a number of clubs this summer, so we're really pleased we managed to sign him on a two year contract" said Williams.
"Ben has a lot of experience at this level and he's bound to be a big player for us."
More to follow.
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