B-Line Eaton series strut channel, 1.62" channel height, 120" channel length, 1.62" channel width, 12 Gauge steel, SH hole pattern, B22 channel type,

SH means the channel is slotted on the back (the closed side), not solid. You get bolt access through the base for through-bolting to structure, hanging threaded rod, or joining channel back to back, without having to field drill 12 gauge steel. If you want an unbroken back for appearance or maximum section, you want the solid version instead of SH.

No. Yellow zinc chromate is an indoor, dry-location finish. It is fine for mechanical rooms, ceiling spaces, electrical rooms, and general interior racking. For roof-mounted runs, parking structures, exterior walls, wash-down areas, or corrosive process environments, order hot dip galvanized or stainless strut instead.

B22 is the back-to-back double channel, two 1-5/8 sections welded together into a 1.62 by 1.62 section, where a single channel of the same width is half the depth. Reach for the doubled section on longer unsupported spans, trapeze hangers carrying multiple conduit runs, or where you need bolt access from both faces. For light single-conduit strapping on a wall, the single-height channel is the cheaper and lighter choice.

Order Eaton B-Line part number B22SH-120BSYZN. That breaks down as B22 double channel, SH slotted hole pattern, 120 inch length, yellow zinc chromate finish. If you are standardizing a job, quote that full string rather than just B22, since the suffix is what fixes the hole pattern and finish.

Yes, 12 gauge steel channel cuts with a bandsaw, chop saw with a metal blade, or portaband. Because the finish is a plated yellow zinc chromate, any cut end is bare steel, so hit it with cold galvanizing or zinc paint and cap it if the run is anywhere humid. Buying the 120 inch stick and cutting is normal practice for trapeze legs.