Aquarium Algae Scrapers 40cm Stainless Steel AISI-420 & 410 (Rock-Well-Hardness 48 – 58) High German Quality Including Protective cover Quality-Tested, Durable The sharp blade frees the glass from algae effortlessly Highly suitable for large and very large aquaria 4 cm wide blade https://simrix.com/product/aquarium-algae-scrapers-40cm/