it's for the view ID of the item, in your item script like this one:
8220,Urahara_Hat,Urahara_Hat,5,5,0,150,,2,,1,0xFFFFFFFF,7,2,256,,1,,952,{bonus bAllStats,1;},{},{}
the # in red is the view id of the item which you added to the accessoryid.lua
If you don't add it in the accessory.lua & accname.lua , expect sprite errors in game if you wear those items with no view ID in lua.
Just follow what the wiki says; I think I don't need to tell you again, on how to add it! =)