HAPPY PIE PLAY&ADVENTURE HappyPie Kids Wall Rock Climbing Holds with Hardware Screw for Children Outdoor Playground 1.Cap screw: 0.47 inch in depth, the depth of the plywood or board should be more than 0.47 inch or the screws will expose on the back if the plywood or board is too thin. Use for indoor & Outdoor climbing. Can be installed on wall and board Set of 5, suitable for 3-7 years old children, let your little child get exercised. Package Included: stones, cap screw, washer, hex key, inner expansion bolt LIFETIME WARRANTY  If these climbing wall holds give you any trouble, ever, we will make it right. That is it. We stand behind our quality and customer service. Know your rock wall will be there to entertain kids for years to come.