Made of T6-6061 Aluminum, Schaefer's Big Boat round batten receptacles include a lightweight, hardcaoat finished backing plate. All models allow for easy attachment to other track systems. The 351-12 fits 12 mm studs for Schaefer slides or competitors systems. Removable nosepiece allows for front-end loading of full battens. Fully adjustable ensures proper batten tension. Fits round battens from 7/16"(11mm) - 1.0" (25mm). Adjustment range 4.5" (114mm), Length 8.5" (216mm) Width 3.05" (77mm)