The gear is matched to the setting and the size of trout you are after, but these setups cover most situations in Argentina:

Spinning (general use, trout of 1 to 3 kg):

• Rod: 1.80 to 2.10 m, medium to medium-fast action, light to medium-light power (casting lures of roughly 3 to 12 g).
• Reel: front-drag, size 1000 to 2500, with a progressive, smooth drag—key to withstanding the runs and jumps without breaking off.
• Line: fine braid of 8 to 15 lb for its sensitivity and lack of stretch, or nylon/mono of 6 to 10 lb if you prefer something more forgiving for the hookset.
• Leader: a section of fluorocarbon of 0.20 to 0.28 mm; fluoro is less visible underwater, which matters in Patagonia's crystal-clear water.

Fly:

• 5-6 weight outfit: the most versatile for river rainbows in Patagonia (dries, nymphs, and small streamers). A 9-foot rod.
• 7-8 weight outfit: recommended for big-trout waters like Strobel/Barrancoso, heavy streamers, and strong wind.
• Leader and tippet: a 9-foot tapered leader finished in 3X to 5X tippet depending on the fly size and how selective the fish is.

For trophy specimens (5-10+ kg at the Strobel): step up the power—medium/medium-heavy spinning with 15-20 lb braid and a robust fluoro leader, or a 7/8 fly outfit—because these are fish with strength and runs far superior to the average trout.

In every case: a well-adjusted drag, sharp hooks (barbless if you are going to release), and a rubber net to handle the fish with the least possible harm.