The Blizzak LM-25-1 RFT (Run-Flat Technology) is Bridgestone's self-supporting run-flat Performance Winter / Snow tire developed to provide temporary extended mobility during winter driving in the event a puncture allows complete air loss. Designed exclusively for the drivers of BMW X1, F30 3 Series sedans and E60 5 Series sedans, Blizzak LM-25-1 RFT Performance Winter / Snow tires allow drivers to maintain their vehicle's sporty appearance and wintertime mobility while providing traction in cold, dry and wet conditions, as well as in snow and on ice. Vehicle ApplicationTire SizeBMW X1sDrive28i225/50R17 89HBMW X1 xDrive28i225/50R17 89HBMW F30 3 Series225/50R17 89H BMW E60 5 Series 225/50R17 89HBlizzak LM-25-1 RFT winter tires feature a directional tread design to enhance hydroplaning resistance on wet and slush-covered roads with rounded tread shoulders to enhance dry and wet road handling. Their tread compound has a high silica content instead of the Multicell tread compounds used on other Blizzak winter tires to combine winter traction with H-speed rated durability (current Multicell compounds can only support up to T-speed ratings). The Blizzak LM-25-1 RFT features an independent block tread design that employs the Lamellen edge effect (multiple biting edges in the tread blocks to help grip snow and ice) to enhance winter traction without resorting to traditional metal studs.Blizzak LM-25-1 RFT winter tires meet the industry's severe snow service requirements and are branded with the three-peak mountain snowflake (3PMSF) symbol.NOTE: Snow platform indicators (the equivalent of snow wear bars) are molded into the Blizzak LM-25-1 RFT's tread grooves to inform the driver when snow traction will be reduced as the tire's treadwear reaches the point where the remaining tread depth becomes less effective in deep snow.Install Bridgestone Blizzak LM-25-1 RFT tires in sets of four only.Due to the traction capabilities of the Blizzak LM-25-1 RFT, Bridgestone recommends using Blizzak LM-25-1 RFT tires only in sets of four to provide the best handling characteristics and tire performance. Related Information: What is the three-peak mountain/snowflake symbol (3PMSF)?