Union La x Nike Cortez 'Lemon Frost'Buy the Union La x Nike Cortez 'Lemon Frost' today. The Nike Cortez, which celebrated its 50th anniversary, was given a new look by the Union LA collaboration in the Lemon Frost edition. The sneaker features a patchwork design with a mix of tan suede and woven textile lavender and hot pink underlays, whose colours represent the diverse culture of Los Angeles. The sneaker sits atop a speckled crater foam midsole and a herringbone traction rubber