C4 Belts are made from environmentally friendly innocuous and nickel free TPE plastic. 100% recyclable; both belts and buckles are available in 20 colors. BOLD Colors : BOLD Statements. Belts are one size fits most and fully adjustable, currently fitting up to a 38" waist. Removable buckles are easily interchangeable with other C4 Belts allowing for up to 400 unique color combinations. Proceeds from this month's sales go to the Boys Clubs of America. Inspiring and enabling all young people to realize their full potential as productive, responsible, and caring citizens.