giving more room to mix intermediate tones directly on the page rather than relying on pre-made shades

They call it "Open Book"

fluid script

This is the same paint that fills OTR squeeze markers and flow pens - now in bulk for when you go through it fast

One cartridge writes 8

pentel mechanical pencil erasers refill 4 pack Sketch giving more room to mixFactory spec eraser refills for Pentel mechanical pencils non abrasive white polymer that lifts graphite without tearing paper fibers. Fits under the push cap of GraphGear 500, GraphGear 1000, Sharp P200 series (P203 P205 P207 P209), and EnerGize pencils. Includes 2 stainless steel mounting pins to anchor the blocks in the lead chamber. Latex free. Contents: 4x eraser blocks, 2x mounting pins Material: Non abrasive PVC polymer, matte white Fits: