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SigmasTek  |  SKU: BW-8737

Merits Pioneer 3 S135 U1 High-Performance Replacement Battery Set 49.45 lb

15% off
New arrival
Sale price $245.99 USD Regular price $287.99
Shipping calculated at checkout.
Includes 2 maintenance-free, spill-proof 12V 35AH batteries
High performance with high discharge design for reliable power
AGM technology ensures long service life and durability
Guaranteed compatibility with original Merits Pioneer 3 S135 U1 batteries
1-year warranty and fast shipping within 1 business day
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Battery Care Tips

🔹 Getting Started

Charge your new battery fully before you use it for the first time. Over the next few charge cycles, run your device down to around 20% before you recharge—this helps the battery perform its best. After that, charge whenever you need to.

🔹 Keep It Healthy

Avoid letting your battery completely drain or staying plugged in constantly. Both extremes wear it out faster. Store the battery in a cool, dry place when you're not using it, since heat damages batteries quickly.

Delivery and Shipping

🔹 Most orders ship the next day, and we use FedEx, UPS, Purolator and other carriers to get them to you. Lithium batteries have to ship by ground only, not air or USPS. Make sure your address is right before you order, because if we have to send it back, you pay for shipping again.

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


Volts & Amps

12 Volts | 35 AH

Terminal Type

Nut & Bolt

Merits Pioneer 3 S135 U1 Replacement Battery (12V 35AH NB) - 2-Pack

Keep your Merits Pioneer 3 S135 U1 wheelchair powered and dependable with this OEM-compatible 2-pack replacement battery set. Designed specifically for the Merits Pioneer 3 S135 U1, these 12V 35AH batteries deliver reliable performance, strong discharge capability, and a wide operating temperature range. If you need a trusted replacement battery that meets or exceeds original specifications, this high-performance battery set offers durability and consistent power for daily use.

Key Specifications

  • Package contains: 2 batteries
  • Volts: 12
  • Amps (AH): 35
  • Weight: 49.4Lbs
  • Length: 7.72
  • Width: 5.14
  • Height: 6.14
  • Terminal: NB (Nut & Bolt)
  • Maintenance-free
  • Spill Proof
  • SLA Chemistry
  • AGM Technology
  • Guaranteed compatibility with original batteries
  • 1-year Warranty
  • Brand: SigmasTek
  • Shipping Methods: UPS Ground and USPS
  • We ship in 1 business day for all in-stock items

Benefits

These Merits Pioneer 3 S135 U1 replacement batteries are engineered to deliver a long-lasting battery life and steady power output that keep your wheelchair running smoothly. The AGM and SLA chemistry provide a maintenance-free, spill-proof design that is safer and more convenient than flooded lead-acid cells. With a high discharge design and wide operating temperature tolerance, this high-performance battery performs reliably under varied conditions, minimizing downtime and keeping mobility devices ready when needed.

Durability is built into every cell: robust construction and proven chemistry extend cycle life so you get consistent capacity over months and years. Typical applications include wheelchair power systems, mobility scooters, and other medical mobility devices where dependable reserve capacity and safe, leak-resistant operation are essential. These batteries are also suitable for emergency backup, light UPS systems, and portable power needs associated with mobility equipment.

Installation is straightforward — replace the batteries in the original configuration and reuse your existing cables. Be sure to verify dimensions against your current batteries prior to ordering, as manufacturer specifications can change.

Ready to restore full mobility? Order this Merits Pioneer 3 S135 U1 replacement battery 2-pack today for a reliable, high-performance battery solution with a 1-year warranty and fast shipping.

Technical Specifications

Voltage12 Volts
Amp Hours35 AH
Terminal TypeNut & Bolt
Length (in.)7.72
Width (in.)5.14
Height (in.)6.22
Weight (lb.)49.4

Product Highlights

  • Brand Replacement : Merits Pioneer 3
  • Manufacturer: SigmasTek
  • Product Type: Medical Equipment Batteries
  • Warranty: 12 Months
  • Bulk Orders: sales@batteryweb.com

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