The series 2800 vinyl sliding window has a fusion welded vinyl frame and sash which creates strong, weathertight corners. Dual weatherstripping virtually eliminates drafts. Durable rollers and a specially designed rolling track make opening and closing these windows easy. Integral J-channel allows for neat, easy trimming of exterior siding to the window. A colonial brickmold design offers a traditional look. Low E3 glass is insulated with argon gas to reduce heat loss. Color matched cam action lock. U-factor is 0.30. Limited lifetime warranty. White.