This is a pair of Pro-Line Edge 2.2" off-road front truck tires in M3 compound. The Edge tread pattern is designed to be an excellent general purpose front truck tire. It will work on just about any track condition, however this tire is best in wetter or loamier track conditions. The drier the track, the harder the compound of tire you should use (ie: M3 when very wet, M2 when dry). However if the track is very dusty, you should generally use a softer compound tire. For hard packed, blue groove tracks it may catch the ruts, so you would be better off using a smaller pin tire on the front, such as the Pro-Line Blades or even Pro-Line Hole Shots.
Pro-Line truck tires are generally available in M2, M3 and R3 compounds. The M2 compound is the hardest compound and will provide the longest tire life and works best on hard packed, dry tracks with high traction. If the track is wetter or less hard packed, the M3 compound tires will provide better grip with decent wear, but will generally wear faster than M2 compound tires. The new R3 rubber compound was designed by Pro-Line to provide the traction of the M3 compound yet the wear characteristics of the M2 compound. The R3 compound generally seems to work best on hard packed, blue groove tracks and is not a good all purpose tire compound (note that not all tire treads are available in R3 compound).