The BC is especially designed for thermoplastic handle type BEUCHAT MARLIN. The fit is sufficiently simple and can be installed easily by any user within 2 minutes..It consists of the best inverted trigger system with mechanical tappets and also includes the loading but for easy arming. Easy installation using the holding pins and line release as in the original handle. It self centers and snaps the rod 8.2cm further back in relation to the classic front mechanism and can accept shafts with extra slots, thereby giving the maximum loading length. It has an excellent line of sight once aiming. The design has been thoroughly studied thus offering sensitivity unaffected by load. The trigger has a short pull route and utilizes the best angle and rotation of the trigger resistance as to produce a smooth and unprecedented trigger experience. The innovative operating system with pushers of the mechanism is patent protected. Any change or modification with respect to the shape, size, dimensions, materials of construction and assembly including a variety of application fields and if it does not include new inventive steps and is not conducive to the technique already known will be considered an aim and aspirations of the present invention. The ideal suggestion to upgrade weapons with type BEUCHAT MARLIN handle.