eForCity Gym Running Sport Armband Case for iPod nano 4 (Black) Exercise your right to a great soundtrack with this ultimate workout duo: an iPod Gen4 Nano compatible Sport Band with Case. This durable, lightweight armband case keeps your iPod secure and protected. Exercise your right to a great soundtrack with this ultimate workout duo: an iPod Gen4 Nano compatible Sport Band with Case.. Provides easy access to all functions without removing the case. Multiple layers of padding offer the best in protection. Armband is compatible with upper arm circumference: 10 - 15 inches. Accessory ONLY. MP3 player not included. Compatible With Apple: iPod nano 4th Gen. 16GB/8GB.