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SigmasTek  |  SKU: BW-15830

MK ES33-12 Reliable Replacement Battery

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

➤ Absorbent Glass Mat (AGM) technology for enhanced performance

➤ Maintenance-free, spill-proof design for hassle-free use

➤ U.L. Recognized and CE Certified for safety and quality assurance

➤ Brand new and factory fresh to ensure reliability

➤ 1 year warranty for peace of mind and guaranteed 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

MK Battery ES33-12 Rechargeable Sealed Lead Acid (SLA) Battery (Replacement) — Compatible with MK Battery ES33-12

When you need a dependable replacement for the MK Battery ES33-12, this MK Battery ES33-12 Rechargeable Sealed Lead Acid (SLA) battery (Replacement) delivers the compatibility and performance you require. Engineered with Absorbent Glass Mat (AGM) technology and a maintenance-free, spill proof design, this replacement battery is a high-performance battery choice for professionals and consumers alike seeking consistent, long-lasting power.

Key Specifications

  • Compatible Model: MK Battery ES33-12
  • Battery Type: Sealed Lead Acid (SLA)
  • Technology: Absorbent Glass Mat (AGM) Technology
  • Voltage: 12 Volts
  • Capacity: 35 AH (Amp-hours)
  • Terminal Type: Nut & Bolt
  • Design: Maintenance-Free with Spill Proof Construction
  • Certifications: U.L. Recognized and CE Certified
  • Condition: Brand New, Factory Fresh
  • Brand: SigmasTek
  • Warranty: 1 Year Warranty

Benefits

This replacement battery combines rugged construction with stable performance to meet the needs of demanding power environments. Its AGM design supports higher charge acceptance and improved cycle performance, making it a long-lasting battery option for both standby and cyclic uses.

  • Durability: Robust, maintenance-free construction and spill proof design ensure safe operation and low upkeep.
  • Long Life: High-quality components and factory-fresh assembly support extended service life and reliable backups.
  • High Performance: Designed to provide steady voltage and dependable discharge characteristics under load.
  • Certifications: U.L. Recognized and CE Certified for trusted compliance with safety standards.
  • Typical Applications: Ideal as a replacement battery for UPS units, emergency power systems, security systems, mobility devices, and tools that use the MK Battery ES33-12 replacement form.

Whether you’re maintaining critical infrastructure or replacing a worn battery in equipment, this MK Battery ES33-12 replacement battery offers a cost-effective way to restore reliable power. It meets the OEM SLA specifications and provides the dependable performance you need.

Ready for dependable power? Purchase this high-performance replacement battery for the MK Battery ES33-12 today and benefit from a reliable, long-lasting battery backed by a 1 Year Warranty.



Payment & Security

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