Here is a list of EVERY part and function on a standard Base Plate Compass. I did an internet search this morning and there wasn’t one single website or video showing “every” part on a Base Plate Compass so I thought it would be interesting to make a video, so at least the information is out there. This is a long video so if you want to fast-forward to a particular feature, here is the order they are described. You can "click" the time to jump to that point in the video. 1. Direction arrow 3:20 2. Luminous pointer 3:50 3. Romer scales 4:15 4. Bezel/dial 5:35 5. Orienting lines 6:09 6. Ruler (imperial) 7:08 7. Magnetic needle 7:30 8. Risers 8:15 9. Lanyard attachment 8:50 10. Orienting arrow 9:15 11. Ruler (metric) 10:00 12. Declination scales 10:15 13. Index Mark / Line 11:35 14. Hole with crosshairs 12:10 15. Parallax Line(s) 12:50 16. Magnifier 14:10 17. Label holder 14:35 18. Sighting hole 17:20 19. Sighting mirror 18:10 20. Sighting Lines (H) 19:25 21. Sighting Lines (V) 19:40 22. Index Line 20:45 Here are the links mentioned in the video: Take UTM coordinates /Grid reference with compass https://www.youtube.com/watch?v=yfcymnPE304 A simple method of dealing with magnetic declination https://www.youtube.com/watch?v=qXCIb-TNBME Slope angle with and without an inclinometer https://www.youtube.com/watch?v=4LR14ue0Gz8