Boot opening measures approximately 6" around Shaft measures approximately 3.1"~6.0'' from arch 【Comfortable Plus Cashmere Lining】-Plus cashmere style is responsible for warming your feet,Kid snow boots,Kid winter boots,Kid hiking boots 【Windproof Boots and Elastic Laces】-Outdoor windproof boots, Made with PU leather waterproof upper,with the bungee type laces,these are great for kids to get on and off.Protected the Kids feet from getting wet ,hiking and trekking through snow 【Skin-friendly Non-slip steel buckle】-The anti-slip steel buckle is designed to meet the special anti-slip requirements such as snow walking shoes and outdoor boys hiking trekking mountaineering. 【Multi-Occasions Multi-function】--These boots can be hiked in snow! Even hike up rocks and over grown trails without a problem. Great traction from the soles. Great support for ankles when hiking.