Retinol Booster — Sample 4ml A lightweight facial serum with two forms of retinol for a smoother-looking complexion. Manufacturer: Beyer & Söhne $19.00 Custom wishlist OK Add to wishlist Qty: Add to cart Email a friend A lightweight facial serum with two forms of retinol for a smoother-looking complexion.How to useIntroduce gradually into your evening routine, following the directions on the product. Use sun protection during the day.