Tough Spots come in rolls of 5000 spots with 5 spots across the rolls. The tough spots come in 1/2" and 3/8" sizes. White or assorted colors are available. The 3/8" Tough Spots are perfect for .5mL and 1.5mL tubes. Use the 1/2" Tough Spots for 1.5mL and 2.0mL Tubes. The assorted roll has 1,000 spots each of Blue, Green, Violet, Red & Yellow.