Empty in-floor ski lockers often sit completely wasted during long surf sessions, but the versatile FatSac Rear Locker Seat Ballast transforms that open space into a pro-level wave-making asset. FatSac engineered this low-profile rectangular profile bladder to function as a multi-position solution that fits cleanly inside ski lockers or directly on rear bench seats. Adding 650 lbs of targeted water weight drives your boat hull deep into the water column, expanding the length of your wakesurf power pocket. Stance alignment remains stable. Every wave lip breaks with absolute clarity.

The rugged vinyl skin uses a proprietary, layered UV-stabilized polyvinyl chloride fabric engineered to tolerate heavy passenger foot traffic without dropping internal pressure. High-frequency welded and seam-taped joints eliminate traditional burst splitting along the edges, keeping your internal hull safe from high-volume leaks. Captains configuring automated drainage lines frequently match these high-flow inset valves with parts in our specialized boat wakeboard package sets inventory to secure fast pumping speeds. Four ports handle clean hose routing.

Key Features of FatSac Rear Locker Seat Ballast

- 650 lbs Target Ballast: Displaces 78 US gallons of water weight to effectively maximize rear-end transom depth or center hull stability.
- Multi-Position Rectangular Profile: Measures 62 x 26 x 10 inches to lay low along rear bench seats or slip inside long in-floor ski lockers.
- High-Frequency Pressure Welams: Fuses all structural joints with taped burst-proof seam technology to handle passengers stepping directly on the skin.
- 4 Inset Valve Ports: Positions two valves on the top surface and one on each end to allow flexible plumbing routing from any angle.
- Turnkey Fitting Setup Pack: Includes two W731, one W749, and one W730 quick-twist connectors out of the box for immediate pump integration.
- Supa Pump 3.0 Compatibility: Links directly with Supa Pump 3.0 and standard 1-inch Tsunami ballast pumping systems for rapid fill cycles.
- Commercial Grade Vinyl Shield: Formulates the heavy exterior skin to resist intense sun baking, compartment scuffs, and chemical engine fuel fumes.
- USA Handmade Precision: Constructs every ballast sac by hand in the USA to guarantee industry-leading material strength and zero factory leaks.

Low-Profile Multi-Zone Ballast & Rear Bench Balancing

This low-profile rectangular sac functions as an exceptional tuning tool for inboard boats that require dense weight without losing passenger seating space. Placing this 650 lbs bag flat across the rear bench pushes the transom down, shaping a steep surf curl.

We verified this 650 lbs rectangular sac performance inside a tight in-floor center ski locker. The four inset valve ports are highly effective, letting us route our fill lines along each end without any kinking or tight hose pinching under the deck plates. It held its pressure perfectly all day, adding serious mid-ship weight that smoothed out our wakeboarding wake.

Why Choose FatSac Rear Locker Seat Ballast

Standard cheap water bags expand into round, rolling logs that slide across the deck, bruising passenger ankles and splitting open during sharp turns. The FatSac Pro-X series bag prevents this safety hazard by packing low-profile rectangular stability and welded burst-proof layers together, providing a safe, high-value summer investment.

Factory Warranty & Professional Care Guidelines

This multi-position ballast sac comes backed by an official 1 Year Limited Manufacturer Warranty covering material and bonding defects. To keep the polyvinyl fabric flexible and protect the valve ports, rinse off lake muck after use. Store the bladder completely dry inside a dark locker.