Rack Seismic Gusset Kit CPI Rack Seismic Gusset kit can be added to any CPI Universal rack to stiffen critical load-supporting joints. Whenever possible the top of the rack should be stabilized using CPI Bracing Kit. Gusset Kit includes: 4 each welded steel bolt-on gussets 8 each 1/2-13 x 1-1/4 in. bolts 8 each 1/2-13 nuts This listing is for Each.