Helix Acrylic Office Ruler 6 inch / 15cm (15006) Clear acrylic will not warp or fade over time Easy to read markings Graduated in both imperial and metric Clear acrylic will not warp or fade over time Graduated in both imperial and metric Clear acrylic will not warp or fade over time Easy to read markings Graduated in both imperial and metric Clear acrylic will not warp or fade over time ^Easy to read markings ^Graduated in both imperial and metric