I have just purchased a BTX and 95mm objective lens together with the Swarovski stay on cases for each part. I can see that they have a looped piece of material on each. Is this for attaching a strap or something else? Forgive my ignorance but I came from a 2005 ATS 80HD which had a SOC with attached strap. Has anyone attached a strap or do you just travel with it in a case? I was thinking for short distances from the car and not for lugging it around all day. Many thanks.