Free, no sign-up — the PDF opens directly.
This is Sherwood's own operating manual for the 410, 107 pages long. It is the full document, exactly as supplied: free to download, with no sign-up.
Richmond Scientific buy, refurbish, test and resell this kind of equipment, so if you are working out whether a second-hand unit will do the job, the figures in the details panel are the ones to check it against.
Sherwood Scientific Model 410 Flame Photometer Operating Manual · PDF · English
↓Download manual (PDF)