The Pilot Acroball 4+1 is a multi-function ballpoint pen with a 0.5mm tip size that also includes a mechanical pencil. The Pilot Acroball 4+1 is refillable The compatible ink refills for the 0.5mm version are Pilot BVRF-8EF.

• Acro ink: This oil-based ink has one-fifth the viscosity of traditional oil-based inks, providing a smooth, skip-free writing experience with rich, vibrant lines. The ink is also water-resistant.
• 5-in-1 functionality: Combines four 0.5mm ballpoint pen colors (black, blue, red, green) and one 0.5mm mechanical pencil in a single barrel.
• Comfort grip: The pen has a non-slip rubber grip with a tire-tread-like pattern, designed to reduce hand fatigue during extended use.
• Durable clip: A sturdy, spring-loaded clip is designed for longevity and can be clipped and unclipped multiple times without breaking.
• Recycled materials: The pen body is made from recycled plastic.