Odorless, water-based ink won't bleed through paper yet marks permanently on almost any surface, including plastic, glass and metal. Patented "Thumb Button Cap" allows one-handed cap release. Rubber comfort grip allows greater control while minimizing writing fatigue. Features Microbanï¿½ antimicrobial protection. Buy 12 black get 2 blue and 2 red free. Marker Type: Permanent; Assortment: N/A; Color(s): Assorted; Tip Type: Fine.