Valve action marker. Durable acrylic nib for the most demanding environmental conditions: surface temperature from -10dgup to + 145. Marks on dark surfaces where traditional markers would not be easily visible. Can be used on rough dirty and greasy surfaces. For use on concrete black pipe aluminium PVC steel & stainless steel rubber and tyres. 10 seconds dry time. Water and UV resistant markings. Permanent markers. Markings last up to 6 months. Metal barrel for construction site durability. Xylene-free paint. IMPORTANT: Shake the marker with the cap on. Remove the cap and carefully pump it up and down until ink flows into the nib.