170021 for Pentair 48 Sq. Tank Lid Assembly Compatible with Pentair Nautilus FNS Plus FNSP48 Pool and Spa D. 24.75 x 22.25 x 21 inches. COMPATIBILITY? Compatible with Pentair FNS Plus FNSP48 Pool and Spa D. DIMENSIONS & WEIGHT? 21 x 19.3 x 1.57 inches/18.2 pounds. PREMIUM CONSTRUCTION & OPTIMIZED PERFORMANCE? Provides stable and efficient operation, just like the original part. Made from top – notch materials for durability and long – lasting performance. Heavy-duty UV-resistant PVC with fiberglass reinforcement. We work hard to manufacture high-quality products and also work hard to treat every customer with care. Thank you for your choice.