Santini Delta Optic is a super-breathable summer jersey made from Polartec Power Stretch. The fabric features 4-way stretch technology for excellent fit and freedom of movement. The back panel is made of Delta material for rapid evacuation of perspiration from the body, ensuring fast drying and great breathability. The model is lightweight, designed specifically for training and performance running, and has a close-fitting cut with unrestricted cut sleeves that grip the muscles without restricting them. The cut of this model is very light.