Unicel | C-4335 | 35 Sq. Ft. Replacement Cartridge Filter – Fits Rainbow 9.25" O/L Systems

The Unicel C-4335 35 Sq. Ft. Replacement Cartridge Filter is a premium-quality cartridge designed to provide superior filtration and long-lasting performance for Rainbow 9.25" O/L pool and spa systems. Engineered with heavy-duty pleated polyester media, this filter efficiently traps dirt, debris, and fine particles while maintaining consistent water flow and system pressure. Its reinforced PVC core and chemical-resistant end caps deliver maximum durability, even under high-pressure operation. Easy to install, clean, and reuse, the C-4335 ensures crystal-clear water and reliable filtration season after season.

Key Features

• 35 Sq. Ft. Filtration Area: Provides efficient dirt and debris capture for small to mid-size pool and spa systems, helping maintain clear, balanced water.

• Direct-Fit Compatibility: Designed as a replacement for Rainbow 9.25" O/L systems, ensuring precise fitment and OEM-level performance.

• Premium Pleated Polyester Media: Made from Reemay® spunbond polyester for superior dirt-holding capacity, strength, and chemical resistance.

• Reinforced Structural Core: Rigid PVC center core maintains shape and performance under pressure, supporting long-term reliability and durability.

• Reusable & Easy Maintenance: Washable pleated design allows for repeated cleaning cycles, reducing replacement frequency and overall maintenance costs.

Product Overview
The Unicel C-4335 35 Sq. Ft. Replacement Cartridge Filter is built for dependable performance and long-lasting water clarity in Rainbow 9.25" O/L pool and spa systems. Designed with precision and durability in mind, this filter features Unicel’s signature pleated polyester media, which maximizes surface area to capture fine particles, dirt, and oils without restricting water flow. Its high-quality materials and construction ensure optimal filtration efficiency and resistance to common pool chemicals.

The C-4335’s reinforced PVC center core provides strength and stability, preventing collapse or distortion during high-pressure operation. Its molded end caps form a tight, leak-free seal, ensuring that every gallon of water passes through the pleated media for effective cleaning. This durable, washable cartridge design makes maintenance simple—just rinse thoroughly and reinstall for continued peak performance.

Ideal for spa and pool owners who demand professional-grade filtration, the C-4335 delivers exceptional reliability and cost efficiency while keeping water sparkling clean. It’s the perfect balance of performance, longevity, and ease of use that Unicel is known for.