This is my double-red-ring 24-105. It is, obviously, twice as bitchin as any single-ring model.
Someone (maybe someone here) suggested that one of those silicon wrist bands work great to stop zoom creep. After a proof-of-concept run with one that was laying around the house, I went out on Amazon or Ebay or someplace and found a 'Thin Red Line', 'Support your local firefighter' one. Looks cool, works great. I also have one on my 400 f/5.6 to dampen up that big, fat, easy-to-turn manual focus ring that I'm always hitting accidentally.
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