5 mm stainless steel parallel double-plate flat tip

Smooth bright white surface works clean for line work

Fully refillable with standard 0

The tricot nib handles different paint viscosities without clogging

built around a 3

pentel pocket brush pen refill cartridges 4 pack hiddenproduct 5 mm stainless steel parallelFour replacement ink cartridges for the Pentel Pocket Brush Pen (GFKP GPP3 series). Push engagement seal swaps cleanly mid session with no leaks. Pigment based black ink waterproof and fade resistant once dry, so watercolor washes or alcohol markers can go over your lines without bleeding or reactivating. Contents: 4x black cartridges Ink: Pigment based, waterproof, UV fade resistant Fits: Pentel Pocket Brush Pen (GFKP GPP3)