Montana Acrylic Empty Markers are high-quality, refillable empty markers with an optimum flow control pump-valve system that allows for accurate handling and application. The transparent marker bodies allow for easy color recognition and assessment of remaining content. The extra-fine .7mm and fine 2mm nib markers hold 8ml of paint or ink. The 15mm, broad 30mm and super broad 50mm (2" wide!) nib empty markers hold 20ml of paint or ink.