THE 9 HOLE - 90 DEGREE ANGLED FLAT PLATE IS AN EXTERNAL FASTENING METHOD THAT REQUIRES NO MACHINING SERVICES. THIS FLAT PLATE CREATES A 90-DEGREE ANGLE BETWEEN PROFILES AND ITS SHAPE REINFORCES THE STRENGTH OF THE CONNECTION. IT IS A DURABLE OPTION THAT IS EASY TO ASSEMBLE AND CAN BE RECONFIGURED AND REUSED. THE SUGGESTED MOUNTING HARDWARE CAN BE FOUND ON THE "SUGGESTED HARDWARE" TAB. TIP: USE DOUBLE OR TRIPLE SLIDE-IN ECONOMY T-NUTS TO SAVE TIME AND MONEY. PRE-LOAD YOUR HARDWARE PRIOR TO CONNECTING PROFILES TO SIMPLIFY YOUR ASSEMBLY.