Description Each refillable paint pen is designed with a steel ball inside, to avoid watercolor or pigment solidification, to make you write smoothly; You should first put the ball into the barrel, then inject the ink, and finally tighten the part of the pen. Features -Color:Transparent -Material:PP,Steel Bead,Sponge -Size:14.00X1.50X1.50cm/5.50X0.59X0.59in -Made of high-end PP, steel bead and sponge materials, durable and can be used for a long time. -Each refillable paint pen is designed with a steel ball inside, to avoid watercolor or pigment solidification, to make you write smoothly -These empty gel pen holders are durable and practical for long-lasting use. -Exquisite workmanship, ensure their popularity and utility at the same time. -Small size, light weight and this refillable paint pen is also very easy for you to carry. Made of high-end PP, steel bead and sponge materials, durable and can be used for a long time. Each refillable paint pen is designed with a steel ball inside, to avoid watercolor or pigment solidification, to make you write smoothly These empty gel pen holders are durable and practical for long-lasting use. Exquisite workmanship, ensure their popularity and utility at the same time. Small size, light weight and this refillable paint pen is also very easy for you to carry.