Grog Driller 04 EMPTY Steel Tip Marker, 4mm

Ships empty, which is the point — you decide what goes in it. The 60 ml body takes your own paint mixes, custom pigment blends and metallic paints, so you're not stuck with whatever colour a factory decided to fill. Keep the fill thick: this is a rollerball marker, and thin inks run straight through the ball instead of laying down a controlled line, so it wants high-viscosity paint. The threaded neck and wide mouth make refilling quick and reasonably clean, and it's built to be reloaded indefinitely rather than used once and thrown out.

Up front is a 4mm Steelball tip: a spring-loaded hardened stainless steel rollerball. Where felt and mohair nibs fray, split and tear apart on rough textures, the steel ball just keeps rolling. Rusty metal, raw concrete, greasy shutters, brick, jagged wood — it holds its shape and keeps laying down a consistent 4mm line. It also works where porous nibs simply fail: wet, dusty and oily surfaces where a felt tip either clogs or refuses to deposit anything. Over time that makes it considerably cheaper than burning through disposable markers on the same walls.

The body is soft flexible plastic, an evolution of Grog's Metal Head platform, and it gives you direct control over internal pressure. Light hand, steady movement: crisp fine strokes. Squeeze harder and you force paint through the ball for long, heavy, glossy drips. With high-viscosity paint that squeeze is doing real work, so it's worth testing your mix on scrap first to learn how much pressure your particular fill needs.

For a ready-made fill, Grog Buckshot 60 RSP paint is mixed specifically for steel ball markers and matches the body volume. Replacement Driller 04 steel ball tips are available separately if you want to swap a fresh tip in or keep dedicated tips for different colours.

Specs:

• Tip: 4mm Steelball stainless steel rollerball, spring-loaded, exchangeable
• Capacity: 60 ml, ships empty
• Body: soft squeezable plastic for flow and drip control
• Refill: threaded neck, wide mouth — takes high-viscosity paints and custom paint mixes
• Surfaces: rusty metal, concrete, brick, wood, glass, plastic; works on wet, dusty and oily substrates
• Made by Grog, Italy