{"product_id":"staedtler-660-20-mars-drafting-arm-for-661-a3-drawing-board","title":"Staedtler Mars Drafting Arm for 661 A3 Drawing Board 660 20","description":"\u003ch2\u003eProtractor Drafting Head For The Mars 661 Boards\u003c\/h2\u003e\u003cp\u003e\u003cstrong\u003eStaedtler Mars 660 20 is a drafting head with two transparent rulers and a protractor dial, made to work with the Mars 661 A3 and A4 drawing boards.\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eWhere the board alone gives parallel lines, the drafting head adds angles. A Stop\/Go push-button lets the head either hold a chosen angle or turn freely, and it clicks into automatic settings at every 1° step. The protractor scales run in opposite directions from 0 to 90°, with extra marks at 7° and 42° for dimetric projection, a common way of drawing objects in technical drawing classes.\u003c\/p\u003e\u003cp\u003eThe two rulers carry double-sided, opposite-running scales, and parallel guide lines on them act as a hatching aid when shading sections. Because the rulers sit at a fixed right angle, right angles can be drawn without lifting the head. Staedtler state that it is made in Germany and is operated with one hand.\u003c\/p\u003e\u003cp\u003eOur listing calls it a drafting arm; Staedtler name it a drafting head.\u003c\/p\u003e\u003cp\u003eSee the matching \u003ca href=\"\/collections\/drawing-boards\"\u003edrawing boards\u003c\/a\u003e, \u003ca href=\"\/collections\/geometry-kits\"\u003egeometry and technical drawing\u003c\/a\u003e tools and \u003ca href=\"\/collections\/staedtler\"\u003eStaedtler\u003c\/a\u003e range.\u003c\/p\u003e","brand":"Staedtler","offers":[{"title":"Default Title","offer_id":50552425087232,"sku":"SR660 20","price":91.14,"currency_code":"AUD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0863\/5419\/8784\/files\/Staedtler_Mars_660_Drafting_Head_660-20_1_Mega_Office_Supplies.jpg?v=1791399642","url":"https:\/\/megaschoolsupplies.com.au\/products\/staedtler-660-20-mars-drafting-arm-for-661-a3-drawing-board","provider":"Mega School Supplies","version":"1.0","type":"link"}