Telix

I ordered the Nashbar Time Trial levers along with their Time Trial bullhorn handlebar, reading that these were a "perfect match". However, the brake levers don't fit snugly on the end of the bar! There isn't any slot for the bar end to slide into or anything. This is the first time I've attempted to set up a system like this - am I just dense? Am I supposed to attach the lever with tape or something? It doesn't seem that secure that way...

Thanks in advance.