90 Degree Joiner to suit Galvanised Box GrateMade from fully hot dip galvanised steel, our joiners are available to suit our box grates in the following sizes: 125mm wide x 80mm deep 150mm wide x 125mm deep 200mm wide x 170mm deep 300mm wide x 170mm deep Used to join 2 lengths of galvanised box grates together on a 90 degree angle, they can be easily screwed on to join lengths together. All that is required is to cut the box on the angle, insert it into the joiner and screw it into place.