Stringdrive Technologies Llc.Stringbike is pioneering in inventing a revolutionary way of getting bikes into motion, completely doing away with conventional chains, derailleurs, gear shift mechanisms and related parts.The heart and soul of Stringbikes uses a uniquely innovative technology: strong, durable and extremely flexible ropes and an accompanying drive-train. Similar ropes are used in fitness training to lift weights and at heavy-duty sailing equipment.Please visit our website: stringbike.com