The tip of the Uni Paint Marker is not coloured when you first buy it. You must therefore pump forward the color during the first use. Start off by shaking the pen thoroughly for about ten seconds. Then take a tissue paper and push the tip downwards against the paper. This will open the tip for the ink to come through. Pump slightly with the tip against the paper and you will start seeing a light flow of paint. Have some patience, eventually it will be fully coloured. We strongly recommend the Uni Paint Marker PX-30 (see link below) - an oil-based industrial pen which is considered by many to be the best tire pen on the market. It is permanent and has an opaque, white color that adheres well to tires and rubber. The cape is 8 mm wide and obliquely cut. It is also available with a finer tip which is called PX-20, PX-21 and PX-201respectively - but there are usually no reason to buy something thinner. As a tire paint pen, it is usually the PX-30 that counts! How to do it