Is the Straight Brass Bulkhead Fitting for Metric Tubing, M774L compatible with stainless steel and copper tubes of different wall thicknesses?

The Straight Brass Bulkhead Fitting for Metric Tubing, M774L is primarily designed for metric tubes and is manufactured from high-quality brass. Compatibility with stainless steel and copper tubes of different wall thicknesses is possible, but depends on matching the tube outer diameter and wall thickness to the fitting’s permitted ranges. The permissible working pressure and leak-tight performance vary with tube OD and wall thickness, so you must confirm that the specific stainless steel or copper tube dimensions fall within the M774L’s accepted tube sizes and pressure ratings. For safe, reliable joints use tubes with the specified OD and wall thickness recommended by the manufacturer and follow LET-LOK® installation guidelines; if in doubt, verify compatibility with supplier technical data or engineering support before installation.

Can the Straight Brass Bulkhead Fitting for Metric Tubing, M774L be used with tube materials other than brass, such as stainless steel or copper, without affecting sealing performance?

The Straight Brass Bulkhead Fitting for Metric Tubing, M774L is manufactured and optimized for use with brass tubing, and its sealing performance, pressure ratings and LET-LOK® gripping action are specified based on brass material properties. Using other tube materials such as stainless steel or copper can be possible physically, but may affect sealing and joint integrity because of differences in hardness, surface finish, ductility and wall tolerances. Stainless steel is harder and may require different ferrule/tube preparation or higher assembly torque to achieve a reliable seal; copper is softer and may deform differently under compression, potentially altering grip and leak-tightness. Because permissible working pressure and sealing reliability depend on tube outer diameter and wall thickness—and on the tube material’s mechanical behavior—you should consult the manufacturer’s compatibility guidance or technical data for approved tube materials and any required assembly changes (torque, ferrule type, or surface finish). If no explicit approval is given for stainless steel or copper, test assemblies under expected pressure/temperature conditions or use fittings specified for those materials to ensure safe, leak-free performance.

Straight Brass Bulkhead Fitting for Metric Tubing, M774L

All products, LET-LOK precision connectors/

Additional information

Material	B – brass (bronze)

The LET-LOK® straight partition fitting is a reliable solution designed for secure and precise connection of metric tubes, ensuring maximum performance in demanding industrial environments. Manufactured from high-quality brass, it combines durability with excellent resistance to corrosion, making it suitable for long-term use in sectors such as chemical and petrochemical processing, pharmaceuticals, energy production, nuclear power, and advanced process engineering. Its robust construction guarantees tight, leak-free connections, supporting system integrity even under challenging operating conditions. The permissible working pressure depends on the tube’s outer diameter and wall thickness, allowing for flexible adaptation to specific installation requirements. Engineered with precision, this fitting provides ease of assembly and disassembly without compromising safety, reducing downtime and maintenance costs. By integrating LET-LOK® technology, it delivers consistent reliability, helping optimize efficiency and ensure uninterrupted operation of critical systems. This makes it an ideal choice for professionals seeking proven performance, safety, and long-lasting quality in fluid and gas control applications.

List of product variants

Article number	Product variant name	Nominal inner diameter	Working pressure [bar]	Enquiry
HM-LM774L-08-B	Partition fitting for 8 mm tube, brass	-	-

The LET-LOK® straight partition fitting is a reliable solution designed for secure and precise connection of metric tubes, ensuring maximum performance in demanding industrial environments. Manufactured from high-quality brass, it combines durability with excellent resistance to corrosion, making it suitable for long-term use in sectors such as chemical and petrochemical processing, pharmaceuticals, energy production, nuclear power, and advanced process engineering. Its robust construction guarantees tight, leak-free connections, supporting system integrity even under challenging operating conditions. The permissible working pressure depends on the tube’s outer diameter and wall thickness, allowing for flexible adaptation to specific installation requirements. Engineered with precision, this fitting provides ease of assembly and disassembly without compromising safety, reducing downtime and maintenance costs. By integrating LET-LOK® technology, it delivers consistent reliability, helping optimize efficiency and ensure uninterrupted operation of critical systems. This makes it an ideal choice for professionals seeking proven performance, safety, and long-lasting quality in fluid and gas control applications.