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My sideburn pop-up trimmer on my Philips Norelco popped out and fell apart into their factory pieces and I am having trouble reassembling the full part. Referring to the smaller pieces of the pop-up trimmer for sideburns part.
@windrunner start off with this guide Philips Norelco Shaver 2100 Installing the pop-up trimmer Replacement - iFixit Repair Guide If that is not the part or device that you are referring to, post some good pictures of what is going on with your Trimmer. EDIT your QUESTION and then use this guide Adding images to an existing question - iFixit Repair Guide to post your pictures.