300-Meter (984ft) Tether Spool

Q: Is a 300m tether prone to tangling? What should I do if it catches on seaweed or propellers?

Tangle Risk: Due to the extreme length, the tether is more likely to form "S" curves underwater, making it more susceptible to complex environments than shorter cables. Best Practices: Always maintain appropriate tension during operation. If the cable becomes entangled in seaweed, use the ROV's own thrusters to slowly "untangle" the path. Never pull the cable with excessive force while it is snagged, as this may tighten the knot.

Q: Is the tether fragile? How much pulling force can it withstand?

High-Strength Material: The tether is reinforced with a high-density Kevlar fiber. Tensile Strength: It can sustainably withstand a pulling force of approximately 100kgf. This is strong enough to safely tow a fully-loaded ROV back to the surface in an emergency.

Q: What are the typical use cases for a 300m tether?

Large Radius Search: When the support vessel cannot get close to the target area, the 300m length allows the ROV to navigate from a distance. Deep Vertical Operations: In waters deeper than 150m, ocean currents often cause the cable to bow. A 300m tether provides the necessary "slack" to ensure the ROV can reach the seabed effectively.

Q: What are the lengths of the connectors on both ends?

Underwater Section (Main Tether) : 300 meters (984 feet). This is the high-strength, Kevlar-reinforced cable that connects the ROV to the spool. Surface Section (Connecting to Remote Controller) : 3 meters (9.84 feet). This is the cable that connects the spool to your remote controller, allowing the pilot to maintain a comfortable distance from the spool during operation.

$1,850.00

The 300-Meter (984ft) Tether Spool is the long-range connectivity solution for the FIFISH V and E-Series. Engineered for deep-sea exploration and large-scale infrastructure inspections, this 300-meter Kevlar-reinforced tether provides the maximum operational radius for your ROV. Available with a standard carton or a rugged industrial hard case, it offers professional-grade durability and organized management for the most demanding underwater missions.

Compatible ROV Models
V-EVO, V6 EXPERT, E-GO

Key Features:

Maximum 300m Range: Enables ultra-deep dives and extensive horizontal surveying for large-scale projects.
Anti-Tangle Kevlar Construction: High-tenacity fibers with a specialized smooth outer jacket to prevent knots over long distances.
Industrial Case Option: Available with a high-impact hard case featuring custom foam inserts for ultimate protection during transport.
100 kgf High-Tension Strength: Reinforced core ensures secure retrieval and stability in complex underwater environments.
Professional Spool System: Heavy-duty rectangular spool designed for smooth deployment and high-capacity storage.

Select Option:

With Carton Case

$1,850.00

With Industrial Case

$2,300.00

Want to customize? Talk to our specialist.

Frequently Bought Together:

Q-iRC | Industrial Remote Controller

$1,850.00

7" waterproof smart industrial remote controller with screen, customizing for all FIFISH ROVs integrated, all-weather mission control.

Learn more

GNSS Locator

$1,600.00

Provides real-time surface coordinates for precise ROV positioning and tracking.

Learn more

Payment Methods

Delivery Method

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Take a Close Look

Compatible ModelV-EVO, V6 EXPERT, E-GO

SpecificationsTether Length: 300 m (984 ft)
Color: Electric Lime
Breaking Force: 100 kgf (220 lbf)
Material: Kevlar
Dimension: 50 × 26 × 26 cm (19.7 × 10.2 × 10.2 in)
Weight: 7.7 kg (17 lbs)

In the Box1 × 300m Tether Spool
1 × 3m Tether

Frequently Asked Questions

Have questions about our underwater ROVs or your order? We’re here to help!

Our customer support is available Monday to Friday: 9:00 a.m. – 6:00 p.m. (UTC+8).Average response time: Within 24 hours.

Which FIFISH ROV models are compatible with this tether? Can it be used with other brands?

This spool is basically compatible with all FIFISH ROV models, including the FIFISH V-EVO, V6 EXPERT, and E-GO. It is designed specifically for the communication protocols and connector types of QYSEA products and is not compatible with other ROV brands.

Why does the ROV require a Tether Spool instead of a wireless connection?

This solves the "underwater radio black hole" problem. Because radio waves do not travel well through water, a physical tether is the only way to support the high bandwidth required for 4K HD real-time video transmission while providing a physical safety line for equipment recovery.

Is a 300m tether prone to tangling? What should I do if it catches on seaweed or propellers?

Tangle Risk: Due to the extreme length, the tether is more likely to form "S" curves underwater, making it more susceptible to complex environments than shorter cables.

Best Practices: Always maintain appropriate tension during operation. If the cable becomes entangled in seaweed, use the ROV's own thrusters to slowly "untangle" the path. Never pull the cable with excessive force while it is snagged, as this may tighten the knot.

Is the tether fragile? How much pulling force can it withstand?

High-Strength Material: The tether is reinforced with a high-density Kevlar fiber.

Tensile Strength: It can sustainably withstand a pulling force of approximately 100kgf. This is strong enough to safely tow a fully-loaded ROV back to the surface in an emergency.

How do I choose the right tether length (100m vs. 200m vs. 300m)?

Selecting the correct length depends on your operational depth and the distance from your deployment point:

100m (328ft): Ideal for recreational diving, swimming pool inspections, and shallow dock or hull surveys.

200m (656ft): The professional standard for most inland waterways. Suitable for river, reservoir, and coastal search-and-recovery operations.

300m (984ft): Professional engineering grade. Required for deep-water dam inspections, long-distance internal pipe surveys, and offshore wind farm foundation checks.

What are the typical use cases for a 300m tether?

Large Radius Search: When the support vessel cannot get close to the target area, the 300m length allows the ROV to navigate from a distance.

Deep Vertical Operations: In waters deeper than 150m, ocean currents often cause the cable to bow. A 300m tether provides the necessary "slack" to ensure the ROV can reach the seabed effectively.

What are the lengths of the connectors on both ends?

Underwater Section (Main Tether): 300 meters (984 feet). This is the high-strength, Kevlar-reinforced cable that connects the ROV to the spool.

Surface Section (Connecting to Remote Controller): 3 meters (9.84 feet). This is the cable that connects the spool to your remote controller, allowing the pilot to maintain a comfortable distance from the spool during operation.

Can I purchase a tether longer than the standard 300-meter (984ft) tether spool?

Yes. QYSEA supports customized tether lengths to meet your specific operational depth and mission requirements. Please contact our team to get more information and tailored solutions for extended-range setups.

Our customer support is available Monday to Friday: 9:00 a.m. – 6:00 p.m. (UTC+8).Average response time: Within 24 hours.