Chimay Cinq Cents - meaning Chimay Five Hundred - or as otherwise called 500ieme anniversaire 1486 - 1986. In 1986, the monks at Abbey de Scourmont decided to honor the Principality of Chimay, which had been founded in 1486, by bottling the Chimay Blanche Trappist Ale in a larger 75cl bottle, appropriately adorned with the title "Cing Cents." After all, without the support of the Prince of Chimay, the Abbey de Scourmont may have never existed.
Basically, it is the same beer as the Chimay Blanche - Triple.