Alvin - Heavy Duty Window Scraper - 5 Blades - Alvin Heavy Duty Window Scrapers are Ideal for scraping paint, putty, caulking, or paper. The Heavy Duty Scraper has a rugged metal body, and fully retractable blade. Alvin Window Scraper Includes five replacement blades. Available in three assorted colors. Alvin is one of the primary sources for drafting supplies and drawing equipment in the country. Creative Coldsnow is a pround retailer of Alvin graphic arts, drafting and fine arts products.