Nike mercurial vortex astro turf trainers junior the nike mercurial vortex astro turf trainers junior are ideal for any youngster to wear whilst practicing their skills the trainers are designed with a synthetic upper construction and padded ankle collar for maximum comfort the lace up fastening promotes a secure fit whilst the rubber studded outsole ensures good grip on synthetic surfaces the football trainers junior nike swoosh branding lace up finish micro fibre up