Product Search › 1-3/8 - 28 UN 1TP1.3728 Image 1 of 1 1-3/8 - 28 UN 1TP1.3728 $580.00 Part identification and A, B, C, and D dimensions listed within the product selection. Dimension reference image below. Quantity: Add To Cart Added! Part identification and A, B, C, and D dimensions listed within the product selection. Dimension reference image below.