Hi Supreme Resistance Strength Bands - 3 Piece Set with Door Anchor - Effective Strength, Reduces Tension, Flexibility, Quickness - Swimming, Water Polo, Surfing, Rehab Etc Prime for dry land workouts, strength training, and rehab. Great for fast twitch muscles, improved flexibility and strength in shoulders allowing you to swim faster, streamline tighter and throw harder. Comes with anchor that securely wedges in top, side or bottom of door giving you 100s of exercise possibilities. Perfect for travel and going on epic adventures. Comes with 3 bands and ranging in thicknesses and a door anchor for a full range of resistance and potential. Tones and sculpts muscle for increased economics in effective strength decreasing muscle tension.