Markel Corp., of Norristown, Pa., presents its WP-510 Thermoplastic Fluoropolymer Tubing, an excellent replacement for quartz in water and air purification systems. The extremely smooth surface of the tubing limits scaling and eliminates breakage of the sleeve during bulb replacement. UV performance is significantly improved compared to the current industry standard WP-400 tubing. Pond, aquarium clarifiers, and purifiers made with WP-510 sleeves provide benefits in performance and ease of service.