[High Quality]: Silicone material, skin-friendly, soft and durable for everyday wear. Smooth, dense, durable and sturdy, yet surprisingly soft. [Two-tone breathing holes]: air holes in the strap make it more breathable, comfortable and lightweight, designed for the gym, picnics, pools, climbing, hiking, camping, travel ...... Perfect for smart watches. [Secure]: Stainless steel buckle secures the strap and prevents it from coming loose and falling off. Locks securely into the watch slot. The high quality stainless steel metal buckle connects the two parts and easily attaches the wristband, protecting your smartwatch well. The Apple Watch Sport Band with Ventilation is made of soft silicone to prevent any skin irritation, skin-friendly, sweat-proof, waterproof, lightweight and super comfortable. Available in a variety of colours for women and men, personalise your watch to suit your style. Choose your favourite colour to match your daily outfit, mood and scene. 38/40/41 mm fits wrists 6.0" - 8.2" (150 mm - 208 mm), 42/44/45/49 mm sizes fit wrists 6.3" - 8.7" (160 mm - 219 mm). Please check your iwatch model and select the right size for you before ordering.