Twin model includes two feather boards with 3/4" miter slot and 1/4" T-track hardware for each unit as well as longer bolts for tandem use. Allows quick and easy parallel height settings while staying securely positioned in one place.Revolutionary new design allows quick and easy parallel height settings, while staying securely positioned in one place. Two additional knobs for quick and easy height settings for different material thicknesses. Feather tips molded with rounded edges that won't mark your material. Injection-molded premium high impact plastic feather boards are stackable for taller stock. Includes two featherboards with hardware for 3/4" miter slot and 1/4" T-track for each unit as well as longer bolts for tandem use.