Pull out all the stops with Easton’s 4MM Full Metal Jacket. 4MM FMJ is an ultra-micro diameter shaft that offers less wind drift and minimizes friction to provides the industry’s best penetration. Precision-made in Easton’s USA factory, FMJ features a lightweight, strong carbon backbone with the added KE and accuracy of a precision -drawn aluminum jacket. 4MM Full Metal Jacket is offered in four spines sizes from 400 to 250 to cover virtually all bowhunting setups. Aluminum 8-32 point outsert come standard.