If you're looking for a replacement window or vent knob, the JR Products 20345 Window/Vent Knob Handle - 1" Black is a great option. Made of durable polypropylene, this knob will fit most applications and comes with a replacement screw. It's a great choice for those who want an easy-to-install, durable, and low-maintenance option. The JR Products 20345 Window/Vent Knob Handle - 1" Black is a great choice for those who are looking for an easy-to-install, durable, and low-maintenance option. Made of durable polypropylene, this knob will fit most applications and comes with a replacement screw. Installation is a breeze, and you'll be able to enjoy your new window or vent knob for years to come.