What does the FR in the part number mean?

The flame retardant case. CSB's datasheet describes the base container as polypropylene to UL 94-HB with a 94-V0 flame retardant version available on request, while the CSB price list marks the FR case standard across the XHRL range. Every XHRL part we sell carries the FR suffix, so the flame retardant case is what ships. Where a submittal has to cite the container rating, ask a specialist to confirm it against the build in writing rather than quoting the base datasheet line.

What does the 360 in the part number mean?

A nominal watts-per-cell figure at the 15 minute rate. The measured value on CSB's datasheet is 372.78 watts per cell to 1.67 volts per cell at 25°C, so the label understates the block by 3.55 percent. That is the widest margin in the XHRL range and it narrows as the parts get bigger: the 410 measures 417.33, the 475 measures 478.17, and the 620 measures exactly 620.00. Size from the datasheet column, not the label, and the badge will never flatter the battery.

Will it fit where a group 27 block sits now?

It will fit with room to spare, which is the opposite of the problem most people have. At 10.28 inches this case is about 1.9 inches shorter than the group 27 XHRL12410WFR and 3.2 inches shorter than the group 31 sizes. Going the other way does not work. Send the tray dimensions with the quote request and the fit gets confirmed against the drawing before anything ships.

Why is there no 30 second figure?

CSB prints a dash in that row for every part in the XHRL range, so there is nothing to publish. If your specification calls for a 30 second rating, the 5 minute column at 667.17 watts per cell is the nearest published basis and a specialist can take the question to CSB in writing. We would rather tell you the row is empty than interpolate a number into it.