★One size★Suitable for head circumference below 59 cm(23.2 in) Applicable to most people. ★Lightweight★ The helmet weighs only 430 g（About 1 LB） Perfect for any outdoor application the lightweight design means that you will not feel tired from wearing a helmet on your head and still retain the same protection required for high-intensity outdoor activities. ★Quick release design★The helmet has an adjustable fitting belt that can be adjusted to the appropriate position Quick release buckle design allows you to put on and take off your helmet quickly. ★Multi-functional installation★headphones, flashlights, etc. can be installed on the side rails The integrated NVG bracket is compatible with most NVG style equipment External hook and loop can carry helmet lamp identification card, etc. ★Double layer protection★The helmet body consists of ABS outer helmet and EPP foam inner helmet High ABS material impact-resistant ventilation holes have good air permeability effect EPP elastic foam can enhance the resistance and protect the head better.