All blue/purple items are UNSEALED once you equip them (if you play WoW they are Bind on Equip items) once you already used them (unsealed)... they will now BIND to you and you cannot trade them to other players or sell it in the Auction House anymore (you can sell them to regular npc though or break them to get gems)
There is a SEALER item in the cash shop... you can buy it to SEAL items that you equiped/unsealed so you can sell it again to other players for higher prices
there is limitation on number of times you can seal an item though
For example: A lvl 24 +7 blue sword (it has 7 sealing left)... a player equiped it and make it bind to him... in order for him to sell it to other players again, he will use now the SEALER item in cash shop... once he will use it the blue lvl 24 +7 sword will have (6 sealing left) now
This post has been modified on Aug 20 , 2010 11:24:05 PM by Enlainzer.