The Castelli Core Women's Tri Singlet (Red/White) is a premium women's triathlon top engineered to deliver exceptional comfort, aerodynamic efficiency, and race-day performance across all three disciplines of triathlon. Designed specifically for female athletes, this high-performance tri singlet combines lightweight technical fabrics, advanced moisture management, an ergonomic women's fit, and practical race-ready features to help you perform at your best during swimming, cycling, and running. Whether you're preparing for your first Sprint Triathlon or competing in demanding Half-Iron and Iron-distance events, the Core Women's Tri Singlet provides the performance, comfort, and reliability trusted by athletes around the world.

Developed using Castelli's decades of expertise in performance apparel, the Core Women's Tri Singlet is constructed from premium lightweight technical fabrics that provide the perfect balance of breathability, elasticity, durability, and aerodynamic efficiency. The advanced material delivers a close-fitting, streamlined profile that minimizes wind resistance during the cycling stage while allowing unrestricted movement throughout every phase of the race. Its soft four-way stretch construction adapts naturally to your body's movements, ensuring complete freedom during swimming, maintaining an efficient cycling position, and supporting a natural running stride.

One of the defining characteristics of this triathlon singlet is its exceptional moisture-management system. As physical intensity increases, the technical fabric rapidly transports sweat away from the skin and disperses it across the outer surface for quick evaporation. This process helps regulate body temperature while preventing moisture accumulation that can lead to discomfort during long races. Following the swim, the quick-drying fabric sheds water efficiently, minimizing additional weight and helping athletes transition smoothly onto the bike without feeling waterlogged.

Specifically tailored for women, the ergonomic anatomical fit follows the natural contours of the female body to deliver superior comfort without restricting movement. The carefully designed panel construction supports the shoulders, chest, waist, and back while maintaining a flattering silhouette and an aerodynamic profile. Unlike standard athletic tops, the women's-specific fit reduces unnecessary fabric movement, helping improve both comfort and efficiency throughout the race.

The sleeveless design plays an important role in maximizing mobility and ventilation. By eliminating sleeves, the singlet allows unrestricted shoulder movement during the swim, comfortable arm positioning while cycling, and a natural arm swing during the run. Increased airflow around the upper body also enhances cooling during hot weather races and demanding training sessions, making the singlet particularly effective in warm climates.

A full-length front zipper provides convenient ventilation control throughout changing race conditions. During steep climbs, high temperatures, or intense efforts, athletes can partially unzip the front to increase airflow and accelerate cooling. When aerodynamic performance becomes the priority, the zipper can be fully closed to maintain a smooth, race-ready profile. This flexibility allows the garment to adapt effortlessly to varying conditions without compromising comfort.

The rear storage pockets are strategically positioned to provide convenient access to race nutrition while maintaining aerodynamic efficiency. Designed to securely hold energy gels, electrolyte tablets, nutrition bars, or other small essentials, these pockets enable athletes to maintain their fueling strategy throughout long-distance races without requiring additional storage solutions. The pocket placement minimizes bouncing during both cycling and running, ensuring contents remain secure and easily accessible.

An elastic waist hem helps keep the singlet securely positioned throughout every stage of the race. This prevents unwanted movement and ensures a consistent fit while swimming, cycling, and running. By maintaining the correct garment position, the elastic hem also improves comfort and reduces distractions caused by shifting fabric during prolonged activity.

Flatlock seam construction further enhances long-distance comfort by minimizing friction against the skin. The smooth, low-profile seams help reduce the risk of irritation and chafing, especially during endurance events where athletes remain in the same garment for several hours. Combined with the lightweight stretch fabric, this thoughtful construction creates an exceptionally comfortable race experience from start to finish.

The bold Red/White color combination reflects Castelli's racing heritage while delivering a modern and energetic appearance. The vibrant red symbolizes speed, determination, and competitive spirit, while crisp white accents provide a clean, professional finish. This striking design enhances visibility on the course and pairs perfectly with Castelli tri shorts, creating a coordinated race kit that performs as impressively as it looks.

The premium technical fabrics are designed to maintain their elasticity, softness, and vibrant colors even after repeated exposure to chlorine, saltwater, sweat, and regular washing. This durability ensures the singlet continues to perform reliably throughout multiple racing seasons, making it a valuable investment for serious triathletes and endurance athletes alike.

Versatility is another major advantage of the Core Women's Tri Singlet. Although engineered specifically for triathlon competition, it performs equally well during duathlons, brick workouts, indoor trainer sessions, cycling training, running workouts, open-water swim practice, and general multisport conditioning. Its lightweight construction and quick-drying properties also make it an excellent choice for athletes who travel regularly for races and training camps.

Every detail of the Castelli Core Women's Tri Singlet (Red/White) reflects Castelli's commitment to innovation, technical excellence, and rider-focused design. From the aerodynamic race fit and advanced moisture-wicking fabrics to the practical nutrition storage, women-specific ergonomic construction, breathable sleeveless design, and premium Italian craftsmanship, this tri singlet is built to help female athletes perform with confidence across every discipline.

Whether you're chasing a personal best, training for your next endurance event, or experiencing the excitement of your first triathlon, the Castelli Core Women's Tri Singlet (Red/White) delivers the ideal combination of lightweight comfort, aerodynamic performance, unrestricted mobility, and long-distance durability. Designed for women who refuse to compromise on quality, it offers the race-ready performance and timeless Italian craftsmanship that have made Castelli one of the world's most respected names in triathlon apparel.