Radius Marker, Mini, 8 in Radius no checkout heat treated and tempered Marked with heat treated and tempered Marked with size (inches and millimeters) and working load limit in tons Ultimate strength equals 5 times working load limit Bolt matte finish makes logo imprints crisper and cleaner the three smaller models will fit conveniently into a shirt pocket All have sturdy friction joints to maintain rigidity and accuracy Precision tools made of rust proof aluminum and anodized for lasting protection The arms are precisely aligned with spring tension joints to guarantee accuracy and rigidity The holder accommodates flat or round soapstone and pencils All are a folding type design