There was a currency named Tix on Roblox, but it was removed and all items that costed tickets were off sale.
Well, this one didn't.
One day, ROBLOX added a new hat called Gentleman's Springhat, and costed 100 tix for purchase. Many players were confused that day, since tickets were removed from roblox. One day later, it now costed 100 ROBUX.
Here it is: