Specifications:- Overall Dimension(LxWxH): 14 3/8" x 10 1/16" x 10 7/16" (36.5 x 25.5 x 26.5 cm)- Size: S- Fits Head Circumference: 21 5/8" to 22 1/16" (55 to 56 cm)- Material: Abs, Eps- Net Weight: 3.53 Lbs (1.6 kg). Package Contents:- 1x Helmet- 1x Carrying Bag- 1x Manual. Notice: - Please measure your head circumference to determine which size is suitable for you before purchasing.