30 to allow the security cover to rest on the upper support beam 24 0017 fig5 illustrates a cross section of a side view of the security cover 30 as fitted onto the upper support beam 24 as may be appreciated the vertical surfaces of the security cover 30 extend to cover the bolts 54 coupling the pickets 28 to the upper support beam 24 any attempt to draw the bolts 54 away from the pickets 28 will be resisted by impacting the vertical surfaces of the cover 30 referring back to fig4 each distal bore 34 amp 36 of the security cover 30 is adapted to match corresponding bores in a supporting post bracket 44 and the upper 30 support beam flange 42 a single bolt 52 is fitted through the cover bore 34 the upper support beam bore 44 and the support post bracket bore 42 the bolt 52 is fitted with a special safety nut 50 the safety nut 50 includes an internally threaded smooth conical head that is coupled to a hexagonal gripping ring the hexagonal ring is adapted to break off the conical head in response to application of torque beyond a threshold this allows for securing the nut 50 to a corresponding bolt 52 followed by breaking off the gripping ring without the.