Mark J. Blair <nf6x at nf6x.net> wrote: Thanks for the McMaster-Carr suggestion, I should have thought of that. I removed the gas struts from my PDP-11/44 and found the following markings: Gas Spring Corp. Colmar, PA 1216166-0-0 22/81/3 (the "1" might be an "I") I measured them, and found a compressed length of about 9.8" and an extended length of 15.25". The threaded studs are 5/16"-24. I can't find the company, and Google turns up nothing with either of the number strings. Nor do the numbers seem to indicate what the specifications might be. Perhaps someone with better Google skills than I have might find something. It is, however, an almost perfect match for McMaster-Carr P/N 4138T55. The big unknown is the extension force. After cleaning and oiling them, one of the bad ones measures about 12 pounds, and the other is about 23 pounds. The 4138T55 is available in 15, 20, 30, 40, 50, 60, 90, and 120 pounds. I made a wild random guess and ordered two of the 30 pound struts, which should be delivered Wednesday (12/29/2021). The 40 pound ones have a seven week lead time, and a pair of 50 pound ones seem way too high. When they arrive, I'll let you know how well they work. Worst case, I will have wasted $20.29 each, plus shipping, and have to wait seven weeks for the 40 pound units, or go whole hog and try the 50 pound ones. Thanks for the help and suggestions. Alan Frisbie