B-Line Eaton series imperial cable tray and ladder, 4" Height, 19.188" Length, 12" Width, Series 2-5 vertical inside bend, Aluminum, 90° Angle, 12" Ra

It's a vertical INSIDE bend, meaning the tray turns upward relative to the cable's bend, so the cables run along the inside of the curve. B-Line part 4A-12-90VI12 is the Series 2-5 vertical inside bend at 90 degrees with a 12 inch radius, for 12 inch wide, 4 inch deep aluminum ladder tray. If your run needs to drop down instead, you need the vertical outside bend fitting of the same width, depth and radius, not this one.

Allow for the fitting's overall run of 19.188 inches in length on the 12 inch radius geometry. That is the dimension to lay out against ceiling height, beams or duct before you commit the straight sections, because a 90 degree bend at a 12 inch radius cannot be squeezed into a shorter gap. Tight clearances usually mean stepping the run with a smaller-radius bend or relocating the transition.

It's aluminum, which is why it gets specified for damp, coastal and mildly corrosive areas where plain steel would rust, and it keeps the fitting light at 5.7 pounds for overhead work. Aluminum also does not share steel's magnetic characteristics, another reason it shows up in data and communications runs. Where the spec calls for hot-dip galvanized or stainless steel tray, match that material instead of mixing aluminum in.

The fitting is UL Classified. That is the classification cable tray carries for use as an equipment grounding conductor, and inspectors on commercial jobs generally look for it on every fitting in the run, not just the straights. Bonding jumpers across the fitting splices are still the installer's responsibility per the job's grounding detail.

Plan on ordering connection hardware separately. What you receive here is the 90 degree vertical inside bend fitting itself, B-Line 4A-12-90VI12, in 12 inch width and 4 inch depth. Splice plates, hardware and any hold-down or hanger supports at the transition are separate line items, so add them to the order with the straight sections.

Eaton B-Line part number 4A-12-90VI12: aluminum Series 2-5 vertical inside bend, 90 degree, 12 inch radius, 12 inch tray width, 4 inch rail height, 19.188 inch overall length, 5.7 pounds, UL Classified. Those are the figures to carry onto a submittal or a weight takeoff for the hanger spacing calculation.