Agency & Law Enforcement Officer Sales Only Benelli Factory collapsible stock for the Benelli M4 shotgun. The telescoping stock on the Benelli M4 allows the user to set the stock in any one of 3 positions depending on the situation. The telescopic stock version of the M4 is a powerful, versatile shotgun, capable of withstanding the toughest use. The telescopic stock can be installed on the factory recoil tube that is under the regular stock.