# Noctura.com > Noctura.com provides detailed information and an online purchase option for Noctura 400, a clinically proven, non-invasive sleep mask therapy designed specifically for diabetic retinopathy and diabetic eye disease. Noctura 400 is a CE-marked (Class IIa), clinically evaluated medical device utilizing low-intensity green light therapy to provide therapeutic benefits for individuals suffering from diabetic eye diseases including diabetic retinopathy and diabetic maculopathy. The device offers a non-invasive, comfortable, and effective treatment option, proven through years of clinical research and substantial patient usage experience. Noctura 400 does not replace standard medical treatments such as laser therapy or intravitreal injections, but can complement these therapies and may reduce the frequency or intensity required. Users are advised to follow recommendations provided by their ophthalmologists. The mask usage is simple: each mask provides therapy for 12 weeks, after which the device needs replacement to maintain continuity of treatment. Noctura offers various flexible purchasing options, including one-time purchases, subscription services, and interest-free instalment plans via PayPal. Additionally, Noctura offers a 30-day money-back guarantee if the mask does not provide satisfactory results. Beyond the UK market, Noctura 400 availability extends to Spain, Portugal, and most of Europe, with additional regions continually being developed. It is available for shipping to the USA. ## Product Information and Purchase Options - [Noctura 400 Sleep Mask Product Page](https://noctura.com/product/noctura-400-sleep-mask/): Detailed product description, pricing, purchasing options, subscription information, and refund policy. - [Information for Patients](https://noctura.com/about/information-for-patients/): Comprehensive guide for patients including safety, usage guidelines, frequently asked questions, and clinical results. - [Who are Noctura 400?](https://noctura.com/about/who-are-noctura-400/): Background information about the company, development of the Noctura 400 treatment, and its clinical evidence base. ## Main Website - [Noctura Homepage](https://noctura.com): Central hub for general information, clinical background, purchasing, and customer support. ## Keywords diabetic retinopathy treatment, diabetic maculopathy, diabetic eye disease, Noctura