See Amsterdam Acrylic Markers three nib sizes! - YouTube
Acrylic Marker 4 mm Phthalo Blue 570 | Amsterdam Acrylics
Royal Talens - Amsterdam Acrylic Paint Marker - 15mm Tip - 20 Colours Available | eBay
Amazon.com: Royal Talens - Amsterdam Acrylic Paint Marker - Small 1-2 mm Tip - Full Range of 30 Colours Available - Single Marker Pen - Titanium White #105 : Arts, Crafts & Sewing
4-color 4mm Intro Amsterdam Acrylic Marker Set @ Raw Materials Art Supplies