Overview: This document provides technical specifications for tube-to-tube twin ferrule fittings, specifically focusing on reducing unions. It includes detailed measurements and part numbers for various sizes of both fractional and metric tubes.

Specifications: The document lists dimensions for reducing unions, including outer diameters (D, D1), inner diameter (d), and various other measurements (B, H, H1, a, a1, b, b1, A, L) in both inches and millimeters. Each configuration is associated with a specific part number (u2-No.).

Data Summary: The tables provide a comprehensive list of reducing union sizes, detailing the compatibility between different tube diameters. The data is organized by tube size, with separate sections for fractional and metric tubes.

Key Information: - The document distinguishes between metric and fractional tubes. - Each entry includes precise measurements necessary for selecting the correct fitting. - Part numbers are provided for easy reference and ordering.