The HI-FLO drainage weeper is designed to maximize flow rate when experiencing low pressure found in window and sliding door sills. Sliding windows and doors are particularly susceptible to water drainage problems in the exposed outer portion of the slider track. Water build-up can cause degradation of the finseal on the underside of the sash, leading to leakage, mildew and jamming due to icing. The cover automatically opens to let water escape, then uses a positive-close action to block drafts and insects from entering the house. Compatible with most window and sliding door designs, HI-FLO reduces water build up and the risk of water damage.