The Big Iron Fishing Pole is a specially-made pole that requires skill to use, but enables the angler to have a better chance of catching fish.
This item does not drop from the monsters that spawn in the area or from the monsters that may spawn from the traps, but will be lootable off the trap itself. The traps often contain level 33 or 34 Drysnap Crawlers, which attack when released. The traps will give you either a few shellfish which are only used for the quest  , the Big Iron Fishing Pole, random vendor trash items, occasionally some random green items, or spawn a hostile level 35 or 36 makrura. This makes it slightly hazardous for level 35s to grind for the pole.
The +20 bonus to fishing skill on this pole is only midway in the fishing poles, but it is better than it may seem. It is the first readily obtainable fishing pole with a good bonus. It is much better than the , the next lesser fishing pole below the nearly unobtainable . It is as good for fishing as , the next better fishing pole, and is available earlier. It is nearly as good for fishing as the , the next better fishing pole beyond that, is available earlier, and is available to both factions.
Getting the , the one much better fishing pole, is extremely competitive, there are only 52 opportunities per year for your character to even attempt to obtain one. At the very least, the Big Iron Fishing Pole is a good interim pole while you pursue this goal.
Also, since this item is a white-ranked non-BoP item, you can auction it, buy it, trade it between characters, or let a friend or one of your alts "borrow" it. You can make a decent income farming these at moderately high levels. It is the best fishing pole that can be purchased.
At fishing skill level 375, the Big Iron Fishing Pole and a +100 fishing lure will give you 495 fishing skill. This is enough to fish in all areas and to not have fish get away in all but the hardest (Tier 10) areas. On the other hand, no fishing skill bonus beyond lures is necessary until the hardest areas, if you keep your fishing skill up.