B-Line B143SS6 Eaton series strut fittings and accessories, .22" Height, 5.37" Length, 3.5" Width, .75lbs, Steel, Flat four hole corner plate | Pre assembled, Stainless steel type 316

The B143SS6 is a type 316 stainless steel flat corner plate, which is the grade specified for marine, coastal, wastewater and chemical exposure where standard plated steel would rust out. If your job is indoor and dry, a plain or electro-galvanized fitting covers it; if the strut run sees salt spray, washdown or chemicals, 316 is the reason to pick this one.

The B143SS6 is supplied as a pre assembled flat corner plate. Hardware to attach it to the channel, bolts and strut nuts, is ordered separately, and on a 316 stainless run you want the fasteners and channel nuts in matching stainless rather than plated steel, otherwise the plated hardware corrodes first and you get galvanic trouble at the joint.

It measures 5.37 inches in length, 3.5 inches in width and .22 inches in height (the plate thickness), and weighs .75 lb. Worth checking against your layout before ordering: the plate needs that much flat, unobstructed channel face on both legs of the corner, so tight nests of strut or fittings crowding the joint can leave you short of room.

Order it as B143SS6, an Eaton B-Line series strut fitting. The SS6 suffix is the 316 stainless version, so if a drawing calls for B143 in plain steel or another finish, that is a different part number and a different corrosion rating.

It is a stainless steel type 316 fitting, catalogued with steel as the base material. That matters when you cut or field modify a fitting: with solid stainless there is no plating to breach, but any fabrication on a 316 part should still be deburred and cleaned so free iron does not start surface rust.