The ketone based ink glides on smoothly and erases just as easily and is low odour to ensure comfort when writing extensively it features a strong acrylic tip that wont bend or retract into the barrel even with heavy use the chisel tip delivers a variable line thickness between 3 7mm to 5 5mm perfect sketching diagrams or creating bold titles features bic print 1754 drywipe low odour alcohol based ink cap security lock ideal for meetings and classrooms large plastic barrel chisel ti