First of all the new B-600 series is visually noticeable from the usual caulking guns by the robust, solid construction and the retractable rod. This technique, where the rod is being “rolled up” like a chain, allows free and easy movement in general, but especially in narrow spaces, like under the bonnet/hood. Still the pressure is 250 KG (electronically limited), which allows easy extrusion of high viscosity polyurethane. To protect the motor and the drive from pollution from outside the body of the gun, it is completely enclosed.