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SigmasTek  |  SKU: BW-13428

Simplex Simplex-429115-Retrofit Compatible Replacement Battery

Sale price $91.99 USD Regular price $137.18
Shipping calculated at checkout.

➤ High performance 12V 35AH SLA battery for reliable power

➤ VRLA sealed technology ensures safe operation in any position

➤ Meets or exceeds original manufacturer specifications for quality

➤ Wide operating temperature range for versatile use

➤ 1-year warranty guarantees durability and customer satisfaction


📦🚀 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 | 35 AH

Terminal Type

Nut & Bolt

Simplex simplex-429115-Retrofit Replacement Battery — Compatible with Simplex simplex-429115-Retrofit

Upgrade your backup power with the Simplex simplex-429115-Retrofit replacement battery — a reliable, high-performance battery designed to meet or exceed original manufacturer specifications. This 12V 35AH SLA unit delivers dependable performance in critical systems, offering a long-lasting battery solution with VRLA sealed construction and UL certification. Whether you are restoring emergency systems or stocking replacement parts, this replacement battery provides the durability and consistent output you expect from quality sealed lead-acid technology.

Key Specifications

  • Model: Simplex simplex-429115-Retrofit
  • Voltage: 12 V
  • Amp Hours: 35 AH
  • Terminal Type: NB (Nut & Bolt)
  • Battery Technology: VRLA (Valve-Regulated Lead Acid) Sealed Battery Technology
  • UL Certification: Underwriters Laboratories (UL) certified
  • Weight: 24.7 Lbs
  • Dimensions: Length 7.72 In × Width 5.14 In × Height 6.14 In
  • Package: Contains 1 battery
  • Compatibility: Guaranteed compatibility with original battery
  • Warranty: 1-year Warranty
  • Source: Sourced by Batterysharks.com
  • Brand Reference: SigmasTek (as listed)
  • Shipping: ETD 3 Business Days; Methods – UPS Ground and USPS; We ship in 1 business day for all in-stock items

Benefits

  • Durability: Built with VRLA technology and a high-discharge design, this replacement battery withstands demanding use and offers safe, sealed operation in any orientation.
  • Long life: Engineered for an extended service life and wide operating temperature range, this long-lasting battery reduces replacement frequency and total cost of ownership.
  • High performance: Delivering stable 12V output and 35AH capacity, the high-performance battery supports reliable power delivery for sensitive equipment and critical systems.
  • Versatile applications: Ideal for UPS systems, emergency power supplies, alarm and fire panels, medical devices, mobility equipment, and power tools that require a dependable sealed lead-acid solution.
  • Safe and certified: UL certified for peace of mind in commercial and residential environments, ensuring compatibility with equipment that demands certified power sources.
  • Easy installation: Nut & bolt NB terminal offers secure connections and straightforward replacement for original Simplex installations.

Ready to restore dependable power? Order your Simplex simplex-429115-Retrofit replacement battery today and enjoy the confidence of a high-performance battery backed by a 1-year warranty and fast shipping from Batterysharks.com. Add to cart now to secure a long-lasting battery for your critical systems.


Payment & Security

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