In the 135mm system we also offer an angle that adjusts between 100 Degree and 165 Degree. This enables awkward angles to be incorporated into the system with a minimum of fuss. As with the standard angles, these fittings should be supported by fascia brackets sited within 150mm of the angle.We recommend using a small bead of silicone around the inside of the gutter at the joint for an even stronger joint.