https://www.pearltrees.com/staydryroof1/item775054662">https://www.pearltrees.com/staydryroof1/item775054662. A top quality roofing system will have them mounted all around the side of the roofline, where upright wall https://agnesogak011493.humor-blog.com/38111294/unknown-facts-about-stay-dry-roofing