7 Shelf Boltless Shelving Adder - 48&quot;W x 24&quot;D - 250 lbs/shelf by Western Pacific. $71.24. 7 Shelf Boltless Regular Add-On Units are designed to use the posts of existing shelf units to create rows of connected shelving. These units DO NOT come with 4 corner posts, but rather contain 2 connector posts. Add-on units allow you to build continuous rows of shelving that are interconnected in runs of multiple units of your choice. - - WOOD DECKS ARE NOT INCLUDED! - - To save you mon...