Baselworld 2014: Zenith Unveils the Second Generation El Primero Lightweight Chronograph in Carbon Fibre . Fitted with a Nomex-covered rubber strap, the El Primero Lightweight is limited to 250 pieces with a retail price of 17,500 Swiss francs, which is equivalent to about US$19,800. That's a tenth less than the first Lightweight model, which was limited to 100 pieces.