5/3/2021 Update: US Mail is still running behind in certain cases (especially MD), but transit times are much improved from the previous few months. If you need your diagram(s) quickly, please select UPS at checkout. We have negotiated a flat rate of $9.95 per shipment. (Residential & Extended Area surcharges are included) East of the Mississippi should receive items in 2-4 business days or less, rest of continental US in 4-6 business days at most. US Mail options still available, but delivery may take longer (days or weeks) . The Estimated Dates you see on the USPS site are not guaranteed. Please don't assume you'll be the exception and get a US Mail shipment in 1-2 days, you'll most likely be disappointed. Thank You for your continued support!