Plastic cover caps for screws, nuts, and bolts are designed to enhance the appearance of a furnishing as well as keeping the exposed fasteners safe from potential damage. They might seem minimal and insignificant, but they are extremely important,   
Protection from elements to improve longevity  
By covering the fasteners, it stops them from being affected by the elements that are found on a desk, in a cupboard or on a worktop. For example, water dropped from a bottle, or sticky oil and crumbs loose in a kitchen cabinet can and will all have negative effects on a metal fastener, causing it to become damaged. This weakens the structural integrity of the furnishing which can obviously cause you much bigger issues down the line. On top of the protection from spillages, plastic cover caps can offer a degree of protection from more physical problems that can be caused at any point on a daily basis. Dropping a tool on top of an uncovered screw could bend it out of shape, causing it to stick out dangerously, and making it difficult to remove if needs must. Cover caps from Insignia Manufacturing are made from highly durable thermoplastics that can sustain pressure from external environmental factors.   
Their appearance matters too  
Seeing the top of a fastener sticking out of the side of a cabinet or causing a bit of an eyesore on a desk in an office is not very appealing. Using plastic cover caps, you can hide these away from sight, while also keeping a neat appearance by matching the colour of the cap cover to that of the furnishing. Finding the right part is also important. One that does not fit securely will not only risk the fastener’s strength by leaving room for liquids to get in, but it just doesn’t look particularly appealing. It will be loose and there is the potential for the cap to come off and expose the nail or screw once again.