Kidneys look like bean seeds and are reddish-brown in color. Its length is 10-12 cm, width is 5-6 cm and thickness is 3 cm. Male kidney weighs 125-170 grams and female kidney weighs 115-155 grams. Its outer side is convex and inner side is concave. The fold in the concave part is called Hilus. The hilus is attached to the ureter. Each kidney is covered by a fibrous connective tissue called the renal capsule or tunica fibrosa. Outside the renal capsule is a fatty layer that protects the kidney from friction. At the tip of the kidney are the cap-like adrenal glands.