Personalized Groovy Retro Floral Sigma Mom T-Shirt. hether you are looking for a thoughtful gift or a stylish addition to your wardrobe, the Groovy Retro Floral Sigma Mom apparel is a perfect choice. Celebrate the special bond of motherhood with this witty and eye-catching design that stands out. Embrace your role as a sigma mama with confidence and humor, and let your apparel reflect the vibrant spirit of motherhood. Wardrobe essential for looking good, 24/7. 5.0 oz., pre-shrunk 100% cotton. Seamless 1x1 rib collar. Shoulder-to-shoulder taping. Double-needle stitched sleeves, bottom hem and front neck. Note: greys are a cotton/polyester blend.