Monofilament Line with 20-Pound Test. The monofilament line has been tested for tensile strength, durability and knot strength. It can be used in all types of fishing conditions including deep sea fishing, offshore fishing, fly fishing, kayaking, surfing, diving, etc. It is also suitable for commercial fishing. The monofilament line comes with a lifetime guarantee against defects. Notably, the company was founded in 1995.