Single, double or triple axes, alone or in pairs, with or without a carousel, Harry Winston has explored every facet of the coveted tourbillon complication. Naturally, the tenth anniversary of this Histoire de Tourbillon called for a suitably impressive piece, which the brand is producing as a limited edition of ten. This is the first watch in the collection to feature four independent tourbillons, symmetrically positioned inside a colossal rectangular case in white gold. Each makes a complete rotation in 36 seconds; their four individual rates are then equalised by three differentials. For even greater precision, the movement is equipped with two pairs of fast-winding barrels that are overlaid, series-mounted and connected to the tourbillons. This ingenious construction ensures superior precision for the hours and minutes display that takes pride of place in the centre.