Former Brentford defender Matt Somner has completed his permanent move to Cambridge United.
Somner, 22, signed on loan for the U's in December under former boss Herve Renard but has impressed new manager Steve Thompson.
The ex-Wales Under-21 man had his deal with the Bees terminated on Monday.
"Every time he's pulled on a shirt for this club he has run through brick walls. That's the kind of attitude you want," Thompson told the club website.
Meanwhile U's midfielder Franco Nacca will see a specialist later this month about his ankle injury.