B-Line Eaton series strut channel, 1" channel height, 120" channel length, 1.62" channel width, 12 Gauge steel, B42 channel type, Stainless steel type

The B42-120SS4 is solid type 304 stainless steel, not a plated or painted carbon channel. That makes it the version to use on wet, washdown, coastal, or chemical-exposure runs where a pre-galvanized channel would rust at the cut ends and bolt holes. Mild steel strut in those environments is where most callbacks come from.

B42 is the shallow, half-height profile: 1 in channel height with the standard 1.62 in width. So the width matches common 1-5/8 in strut, but the depth is half of the full 1-5/8 x 1-5/8 section. Use it where you need a low-profile run tight to a wall or deck and the load is light to moderate; step up to a full-depth channel for long spans or heavy trapeze work.

Order B42-120SS4. That number breaks down as B42 profile, 120 in length, SS4 for type 304 stainless. If the existing run on your facility is stainless but full depth, the number you want is the 1-5/8 x 1-5/8 profile instead, not B42, so check the depth of what is already hung before standardizing.

The B42-120SS4 is type 304, which covers most indoor wet areas, food processing rooms, kitchens, and general corrosion service. If the run is in direct salt spray, a pool chlorine room, or an aggressive chemical process, spec a 316 channel instead. Mixing the two on one run is fine mechanically, but do not pair stainless channel with plain carbon-steel nuts and bolts or you will get galvanic corrosion at every connection.

The B42-120SS4 is supplied as a general-purpose steel support channel with no certification applied to the product itself. Specifiers on electrical work normally reference the raceway support requirements in the installation code rather than a listing on the channel, so confirm span and support spacing against your drawings.