Pilot FriXion Ball Knock Retractable Erasable Gel Ink Pens, LFBK-23EF-R, 3-pack
The diameter of a lead : Extra Fine Point 0.5mm, 3 Color Set
Pilot Gel Ink Refills for FriXion Erasable Gel Ink Pen, LFBKRF-30EF, 3-pack
It is a ball point pen that can be erased even if you write it by mistake, Since it is a set of replacement core with the main body, it is relief even if the ink runs out