SeaKnight NT40 Monofilament Nylon Fishing Line | 25–200lb

The SeaKnight NT40 is a heavy-duty monofilament nylon fishing line available from 25lb through to 200lb, covering applications from general heavy tackle through to high-strength leader and trace setups.

The range spans diameters from 0.40mm to 1.39mm, with 100m spools across the 25–120lb range and 50m spools for the heavier 150–200lb options. The supplier describes the NT40 as abrasion resistant and fast sinking.

Key Features

Monofilament nylon construction
Heavy-duty 25–200lb strength range
0.40–1.39mm diameter options
100m and 50m spool lengths depending on strength
Supplier-stated abrasion-resistant construction
Fast-sinking characteristics
Suitable for mainline, leader and heavy trace applications depending on selected strength
Broad range of line classes for freshwater and saltwater tackle

Heavy-Duty Nylon Construction

The NT40 is constructed from monofilament nylon, providing a single-strand line suitable for a range of fishing applications.

With breaking strains extending to 200lb / 90.8kg, the heavier options can be used where substantially thicker and stronger leader material is required.

Line Size & Strength Guide

Size	Diameter	Strength	Spool Length
6.0#	0.40mm	25lb / 11.35kg	100m
8.0#	0.50mm	35lb / 15.89kg	100m
10.0#	0.52mm	40lb / 18.16kg	100m
12.0#	0.57mm	50lb / 20.70kg	100m
14.0#	0.62mm	60lb / 27.24kg	100m
16.0#	0.66mm	70lb / 31.78kg	100m
18.0#	0.70mm	80lb / 36.32kg	100m
20.0#	0.76mm	90lb / 40.86kg	100m
24.0#	0.81mm	100lb / 45.40kg	100m
30.0#	0.90mm	120lb / 54.48kg	100m
40.0#	1.05mm	150lb / 68.61kg	50m
50.0#	1.17mm	180lb / 81.72kg	50m
60.0#	1.39mm	200lb / 90.80kg	50m

Suitable Fishing Applications

The broad strength range allows the NT40 to be selected for different applications depending on the target species, fishing environment and complete tackle setup.

Potential applications include:

Barramundi
Mangrove jack
Large tailor
Spanish mackerel
Cobia
Samson fish
Kingfish
Large demersal species
Reef fishing
Bottom fishing
Boat fishing
Rock fishing
Heavy leader setups
Shock leader applications
Heavy trace material
General freshwater and saltwater fishing

The lighter 25–50lb options provide more manageable diameters for general heavier fishing, while the 60–120lb range moves into heavier leader applications. The 150–200lb options are substantially thicker and are better suited to specialised heavy leader or trace applications rather than general-purpose mainline use.

Specifications

Brand: SeaKnight
Series: NT40
Line Type: Monofilament Fishing Line
Material: Nylon
Strength Range: 25–200lb
Metric Strength Range: Approx. 11.35–90.80kg
Diameter Range: 0.40–1.39mm
Spool Length: 100m / 50m depending on selected strength
25–120lb Options: 100m
150–200lb Options: 50m
Supplier-Stated Characteristics: Strong, Abrasion Resistant, Fast Sinking

Please Note

The 25–120lb options are supplied in 100m lengths, while the heavier 150lb, 180lb and 200lb options are supplied in 50m lengths, according to the supplied sizing chart.

Line diameter increases substantially across the range, from 0.40mm at 25lb to 1.39mm at 200lb. Check reel capacity, terminal tackle compatibility and intended use before selecting the heavier line classes.

Breaking strain, diameter and performance characteristics are supplier-stated specifications. Actual suitability will depend on the selected line strength, knots, terminal tackle, target species and fishing conditions.