The JackCap XLR-F is a soft silicon rubber cap that sits on top of your mixing desk covering your unused female XLR input / outputs to stop dirt and debris getting inside them meaning they will be clean and like new when you do come to use them, the caps simply push down into the hole and then easily pull back out again when needed, they are not a super tight fit so these are not suitable for a desk thats goes to gigs etc, they are ideally for studio use, because of this limitation I have done a discount on the price from 70p each to 50p each for a limited time, 
they are available in black or red and sold loose so you can order the exact amount you require starting from just one single item. 
www.Jackcap.co.uk