Simply place the drain shield over the drain hole inside your planter! The CPR Drain Shield improves drainage for healthy plants. The CPR Drain Shield is the newest innovation for ensuring that your planters are draining properly. CPR stands for Contained Plant Respirator. Simply place it over the drain hole in your planter and add your potting mix. The unique design turns one drain hole into 10 and prevents the potting mix from compacting into the drain hole which prevents excess water from draining out of the planter. Excess water being retained in the planter can lead to mold issues and root rot which can kill your plants. CPR Drain Shield improves the aeration of the root system and helps disperse the fertilizer and protect the root ball when bottom feeding. Healthy roots make for healthy plants. satisfaction guaranteed. made in the USA. Patents pending.