Adjustable seal for sliding doors and windows

A system comprising:

• a sliding window panel configured to slide along a support surface between an open position and a closed position;
• an adjustable seal engaged to a bottom side of the sliding window panel facing the support surface, wherein the adjustable seal includes:
• an elongated base, first and second elongated seals mounted to the base and spaced apart from one another along the base, and an elongated brush mounted to the base that extends through the space between the elongated seals;
• first and second fastener assemblies for engaging respective opposite ends of the elongated base to the sliding window panel, the first and second fastener assemblies each including:
• a fastener extending through the elongated base to engage the sliding window panel;
• a spring between the base and the window panel;
• and
• wherein the spring of each fastener assembly is adjustable with the fastener to position the respective opposite end of the base relative to the bottom of the sliding window panel so the first and second seals are each positioned against the support surface at each of the opposite ends of the elongated base.