Brand: FATH Item: Roll-in nut Series: 15 Series and 40 Series For Use With: All 1.5in, 3in, 40mm and 80mm profile T-slotted rails Material: Zinc plated steel Color: Silver Quantity per Pack: 10 Manufacturer Part Number: 09633U1/4 Thread Size: 1/4-20 UNC Slot Size: 8 FATH roll-in nut, silver, 1/4-20 UNC, zinc plated steel, slot size 8. Package of 10. For use with all 1.5in, 3in, 40mm and 80mm profile T-slotted rails. Manufacturer part number: 09633U1/4.