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SigmasTek  |  SKU: BW-18212

Kawasaki Jet Ski JS300 SX 300CC 1986-1991 High Performance Replacement Battery

Sale price $59.98 USD Regular price $82.13
Shipping calculated at checkout.

➤ Maintenance-free AGM design eliminates acid refills

➤ Spillproof and leakproof for safe, hassle-free use

➤ U.L. recognized and CE certified for quality assurance

➤ Extreme resistance to freeze, heat, and vibration

➤ Superior starting power with deep cycle capacity


📦🚀 FAST SHIPPING: Usually ships same day if ordered before 2 PM EST

⚠️ Quick Reminder

🔹 Please ensure the original battery model number is listed in our product description and that your device model number matches for compatibility.
🔹 We only supply the batteries shown in the images. Device images are provided for reference only.

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Battery Care Guide

Battery Usage and Maintenance Guidelines 🔋

Please read the following instructions carefully before using your new battery. Proper adherence will help ensure optimal performance and extended service life.

1. Cordless Phones, PDAs, and Power Tools (NiMH, NiCd, Lithium-Ion) 📱

Initial Charge

  • Fully charge the battery overnight prior to first use.

Conditioning (First 2–6 Charge Cycles)

  • Operate the device until the battery reaches approximately 20% capacity.
  • Avoid premature recharging.
  • Do not allow the battery to fully discharge during the initial cycles.

Post-Conditioning

  • Recharge the battery only when necessary.
  • These batteries are capable of approximately 500 charge cycles:
  • Once daily → ~500 days
    Twice daily → ~250 days
    Note: Even a partial recharge is considered a full cycle.

2. Sealed Lead Acid (SLA) Batteries 💡

  • No conditioning required.
  • Maintain the battery in a fully charged state; avoid complete discharge.
  • Capable of 300–400 charge cycles.
  • Expected service life: 2–3 years, depending on usage conditions.

3. Laptop Batteries (Lithium-Ion) 💻

Initial Charge

  • Fully charge the battery overnight prior to first use.

Conditioning (First 2–6 Charge Cycles)

  • Charge fully, then discharge to approximately 20% capacity.
  • Avoid complete discharge, as some devices may not detect a fully drained battery.

Post-Conditioning

  • Minimize frequent plugging and unplugging.
  • Allow the battery to discharge moderately at least once per month to maintain optimal performance.
  • Occasional cycling is recommended to sustain battery health.

Professional Recommendation

Adhering to these guidelines will enhance battery longevity and ensure reliable performance.

For further assistance regarding your battery or order, our customer support team is available to provide guidance.

Delivery and Shipping

Everything You Need to Know About Shipping with BatteryWeb (USA)

We know reliable delivery matters when you need power fast. Here’s how BatteryWeb makes shipping easy across the USA:

🚚 Shipping & Delivery

Most orders ship next business day (some products like sealed lead acid may take a little longer).

Same-day shipping available if you order before 11:59 AM (delivery depends on the carrier).

We ship nationwide using FedEx, UPS, USPS, DHL, and regional ground carriers.

Shipping costs are calculated automatically at checkout based on weight, distance, and carrier.

Transit times shown are estimates only (business days, no weekends/holidays).

🌍 Shipping Restrictions

Lithium batteries cannot be shipped by USPS or air. They must go via FedEx Ground, UPS Ground, or DHL Ground.

PO Box deliveries are only available via USPS.

At this time, we do not ship lithium batteries to Puerto Rico. NiMH, NiCd, and Alkaline can be shipped.

📦 Important Notes

Double-check your shipping address! If an incorrect address is used and the order is returned, re-shipping costs are the buyer’s responsibility.

If a product is temporarily out of stock, we’ll notify you right away with the expected restock date—or issue a refund if you prefer.

💲 Currency & Pricing

All prices are shown in USD.

Orders shipped outside the USA may be subject to local taxes, customs fees, or import duties. These are the buyer’s responsibility.

⚡ At BatteryWeb, we’re committed to getting your batteries delivered quickly, safely, and affordably—so you’ll always have the power you need, when you need it.

Disclaimer

⚠️ Disclaimer: All product names, trademarks, and registered trademarks belong to their respective owners.

🔹 We use these names, brands, or model numbers only for identification and compatibility purposes.

🔹 Our products are generic replacement parts and are not affiliated with, endorsed by, or manufactured by the original equipment manufacturers (OEMs).


Volts & Amps

12 Volts | 18 Ah

Terminal Type

Nut & Bolt

Kawasaki (Jet Ski) 300CC JS300 SX (1986-1991) Replacement Battery

Built for marine and watercraft applications, this compatible replacement battery for the Kawasaki (Jet Ski) 300CC JS300 SX (1986-1991) is an AGM maintenance-free solution that delivers reliable starting power and exceptional resistance to harsh environmental conditions. The sealed, spillproof design eliminates the need for acid filling and minimizes maintenance, giving you peace of mind whether you’re enjoying recreational rides or relying on your watercraft for work.

Key Specifications

  • Compatible Model: Kawasaki (Jet Ski) 300CC JS300 SX (1986-1991)
  • Design: Maintenance-Free Design
  • Safety: Spillproof and Leakproof Design
  • Certifications: U.L. Recognized and CE Certified
  • Technology: Absorbed Glass Mat (AGM) Design
  • Ventilation: Valve Regulated Vent System
  • Durability: Extreme Freeze, Heat and Vibration Resistance
  • Performance: Superior Starting Power and Deep Cycle Capacity
  • Condition: Brand New, Factory Fresh
  • Warranty: 6 Month Warranty
  • Brand: SigmasTek
  • Voltage: 12 Volts
  • Capacity: 18 Ah
  • Terminal Type: Nut & Bolt
  • Application: Kawasaki

Benefits

  • Durability: Engineered with an AGM design and a valve-regulated vent system, this battery stands up to moisture, temperature swings, and vibration common to marine environments.
  • Long Life: Maintenance-free construction reduces upkeep and helps ensure a long-lasting battery that keeps your Jet Ski ready for the season.
  • High Performance: Optimized for high-rate discharge, this high-performance battery supplies the strong cranking amps needed for quick, reliable starts even after periods of inactivity.
  • Vibration and Temperature Resistance: Extreme freeze, heat and vibration resistance preserve performance through rough rides, trailer transport, and exposure to sun and water.
  • Versatile Applications: While designed for the Kawasaki JS300 SX, this long-lasting battery can also serve in other demanding 12V applications such as compact UPS systems, emergency backup power, and 12V tools used in field service and marine maintenance.
  • Safe & Convenient: The spillproof, leakproof design and factory-fresh condition make installation safe and straightforward, ideal for seasonal maintenance and quick replacements.

Don’t wait until your Jet Ski leaves you stranded — replace the battery with this reliable, high-performance replacement battery today. Order now to secure dependable starting power and enjoy hassle-free performance backed by a 6 month warranty.


Payment & Security

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