Ceragon Networks Ltd. /zigman2/quotes/206067672/composite CRNT -1.50% shares surged in the extended session Monday after Aviat Networks Inc. /zigman2/quotes/205144234/composite AVNW -1.72% offered to acquire the wireless telecom equipment company and shake up its board. Ceragon shares rallied more than 20% after hours, following a 5.4% decline to close the regular session at $2.09, for a market cap of $176 million. Aviat, which owns more than 5% of shares already, offered $2.80 a share in cash for the shares of Ceragon it does not already own. Ceragon also said it wants to increase the number of board members to nine, while removing three current directors, and appoint five board members. “Aviat believes Ceragon’s current board has overseen destruction of shareholder value and overlooked opportunities to create greater value,” the company said. Ceragon shares declined 1.5% after hours, following a 2.1% decline to close at $25.38.