Drop in a PDF, type the pages you want to remove (for example 2,5-7), and download a fresh PDF with those pages taken out and the rest left in order. Everything happens in your browser, your file is never uploaded, so it is safe for confidential drawings. No signup, no email, no watermark.
Click a page to mark it for removal. Marked pages grey out with a red cross and drop from the count. Click again to keep it. Then download the rest.