{"product_id":"twsbi-eco-580-stub-nib","title":"TWSBI Eco \/ 580 + 1.1 Stub Nib Unit","description":"\u003cp\u003e\u003cmeta charset=\"utf-8\"\u003e\u003cspan id=\"docs-internal-guid-6fad9f3a-7fff-c808-5b43-c61abaceb4cd\"\u003eTWSBI is known for transparent demonstrator bodies and piston-fill mechanisms at an accessible price point, but the real reason it earns this slot is the nib unit system: the nib, feed, and housing come as one self-contained unit that unscrews and swaps in seconds, with no special tools. Once a customer owns one Eco or 580 body, adding a 1.1 Stub nib unit doesn't mean buying a second pen — it means buying a second nib. That's a genuinely different value proposition from most stub pens, and it directly answers the progression gap left once a letterer outgrows the Parallel.\u003c\/span\u003e\u003c\/p\u003e","brand":"TWSBI","offers":[{"title":"Default Title","offer_id":53417233973576,"sku":null,"price":0.0,"currency_code":"GBP","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0935\/0709\/2808\/files\/TWSBIEco_580_1.1StubNibUnit.png?v=1782828478","url":"https:\/\/inkwellartsupplies.com\/products\/twsbi-eco-580-stub-nib","provider":"Inkwell Art Supplies","version":"1.0","type":"link"}