Cliff Keen E58 Headgear The new andquot;cliff keen signatureand#8482;andquot; 4-strap foam headgear is based on the revolutionary design of the original foam e41 that cliff keen patented nearly 50 years ago.andnbsp; lightweight, more comfortable fit and greatly reduced friction on the mat. fully adjustable. sp94 chin strap pad included. can be adjusted to fit youth sizes too.