Contract Altro Classic 25 Graphite X2546R11 Speckled Effect Non Slip Commercial Vinyl Flooring. Tried and trusted for over 60 years, Altro Classic 25 is a 2.5mm flooring that provides lasting slip resistance, durability and abrasion resistance, along with comfort underfoot. It is ideal for use in heavy traffic areas - particularly with wheeled traffic. It is also good for areas where occasional moisture and dust can increase the risk of slipping as it has a Pendulum Test Value rating 45 and an R11 slip rating. For other heavy duty solutions see Altro Atlas 40 and Altro Reliance 25.