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SigmasTek  |  SKU: BW-17305

STX20L-BS High Performance Replacement Battery for Yamaha 660 YFM66FA Grizzly 2002-2008

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

➤ Direct replacement for STX20L-BS battery ensuring perfect fit

➤ Meets or exceeds OEM specs for reliable starting power

➤ Designed specifically for Yamaha YFM66FA Grizzly 2002-2008 models

➤ Durable construction withstands harsh off-road conditions

➤ Provides consistent performance for 660CC engine demands


📦🚀 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.
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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

STX20L-BS Battery — Replacement for Yamaha YFM66FA Grizzly 660 (2002–2008)

Replace your old battery with the STX20L-BS replacement battery designed specifically for the Yamaha YFM66FA Grizzly 660 (2002–2008). This high-performance battery delivers reliable starting power and long-lasting durability tailored for the demands of a 660CC engine. Engineered to meet or exceed OEM specifications, it ensures a perfect fit and consistent performance across seasons and terrains so you can trust your ATV to start when it counts.

Key Specifications

  • Model: STX20L-BS
  • Compatible Models: Yamaha YFM66FA Grizzly (2002–2008)
  • Designed For: 660CC engines
  • Brand: SigmasTek
  • Voltage: 12 Volts
  • Capacity: 18 Ah
  • Terminal Type: Nut & Bolt
  • Design Notes: Maintenance-free construction; meets or exceeds OEM specifications
  • Performance Notes: Reliable starting power even in extreme temperatures; durable construction

Benefits

  • Durability: Robust build quality and enhanced vibration resistance ensure the battery survives off-road conditions and repeated use.
  • Long Life: Maintenance-free design and reliable internal construction reduce upkeep and extend service life, making this a true long-lasting battery for your Grizzly.
  • High Performance: Delivers strong cranking current to start 660CC engines reliably, even after exposure to cold or prolonged inactivity.
  • Perfect Fit: Guaranteed to fit Yamaha YFM66FA models from 2002–2008 for easy, worry-free replacement.
  • Versatile Use: Ideal as a replacement for ATV power needs and also suitable for emergency power, small UPS systems, or power tools that accept a 12V battery replacement.
  • Maintenance-Free Convenience: Spend less time checking fluid levels and more time on the trails with a sealed, hassle-free battery.

Ready to restore dependable starts to your Yamaha Grizzly 660? Choose the STX20L-BS high-performance battery for a durable, long-lasting battery upgrade built to OEM-level standards. Add to cart now and ride with confidence.


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