Ink tank holds free-flowing liquid, permanent fluorescent ink. Barrel has a clear window to monitor ink supply. Cap has a plastic clip. Liquid ink delivers longer write out than reservoir style markers. Will not smear, smudge, or fade. Push down tip to restart ink flow if left uncapped. Highlighter Style: Pen; Highlighter Ink Color: Fluorescent Yellow; Color Family: Yellow; Highlighter Tip Type: Chisel.