Elastic + Drawstring Pants versus Only Drawstring Pants
Karate uniforms with Elastic Pants commonly include a drawstring to ensure the pants do not fall during training. An elastic band is embedded on the waist of the uniform to help keep pants secure.
Some uniforms only have a drawstring and no elastic band, this will only have a draw string to tie the pants on at your desired position. Heavier uniforms commonly exclude the elastic band, and only have a thicker drawstring because at heavier weights, the thicker drawstring is more effective and more secure.