12 Volt 21 Watt Sealed Lead Acid Rechargeable Battery
Item #: SLA-HC1221W   |    Out of Stock

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12 Volt 21 Watt Sealed Lead Acid Rechargeable Battery

Item #: SLA-HC1221W   |  Out of Stock

Today's Price: $19.95

Price: $19.95

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1 Year Warranty
Brand New
100% Compatibility
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Product Specifications for 12 Volt 21 Watt Sealed Lead Acid Rechargeable Battery

BM Part #: SLA-HC1221W
Voltage: 12 Volt
Capacity: 5.5 Ah (21 Watts Per Cell)
Type: Sealed Lead Acid
Length: 5.50"
Width: 1.89"
Height: 4.07"
Shipping Weight: 5.00Lbs
Warranty: 1 Year
Rechargeable: Yes
  • Terminal Plug-in Positive Terminal is F2 (1/4") and negative Terminal is F1 (3/16")
  • Rechargeable
  • Recyclable
  • No Memory Effect

Product Description

Brand New First Quality Factory Direct

If you are using these batteries for a UPS please verify the quantity needed by looking in the owners manual, checking inside the UPS or calling us.

Sealed Maintenance Free

The valve regulated, spill-proof construction of this battery allows trouble-free, safe operation in any position. There is no need to add electrolyte, as gases generated during charging are recombined in a unique "oxygen cycle".

Long Service Life

A dependable service life can be expected under normal operating conditions.

Long Shelf Life

Low self-discharge rate allows for storage of fully charged batteries for longer periods of time before charging is required. Lower storage temperatures will further extend shelf life.

Wide Operating Temperature Range

May be discharged over a temperature range of -40°C to +60°C (-40°F to +140°F), and charged at temperatures ranging from -20°C to +50°C (4°F to +122°F).

Rugged Construction

The high-impact resistant battery case is made either of non-conductive ABS plastic or styrene. Large capacity batteries frequently have polypropylene cases, all of these materials impart great resistance to shock, vibration, chemicals and heat.


  • RBC10, RBC21 equivalent Also replaces APC BF400
  • 12V 5.5Ah
  • Length 5.50 in.
  • Width 1.89 in.
  • Height 4.07 in.
  • Terminal Plug-in Positive Terminal is F2 (1/4") and negative Terminal is F1 (3/16")
  • 1 Year Warranty
  • APC Installation: (Adobe PDF)

4 Reasons Why You'll Love Our AGM Sealed Lead Acid Batteries

  • Sealed, Maintenance Free: Completely spill-proof and can be installed in any position, except upside-down.
  • Fully Charged and Ready to Go: Right out of the box, this 12 Volt, 5.5 Ah (21 Watts Per Cell) rechargeable sealed lead acid battery is ready for anything.
  • 100% Brand New and Factory Fresh: We receive new shipments daily, ensuring each of our SLA batteries are as fresh as possible when you need them.
  • 100% Satisfaction Guaranteed: We back all our batteries with our 60 Day Money Back Guarantee and our SLA batteries include a 1 year warranty.

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Cross Reference

The 12 Volt 21 Watt Sealed Lead Acid Rechargeable Battery has been cross-referenced to be compatible with or replace these OEM part numbers and models:

Customer Reviews

20 Reviews | 4.8 out of 5
5 stars (17)
4 stars (2)
3 stars (1)
2 stars (0)
1 star (0)
Would recommend this product.
What our Customers are saying
Worked as advertized
June 4, 2019
by on June 4, 2019

Plugged battery into UPS and no problems to date.

Would recommend to a friend?
Great generator battery
November 18, 2017
by on November 18, 2017

Couldn't find an original match. Sooo as usual I went to BatteryMart and found a great replacement at 1/3 of the cost of.. Dropped In and works great.. Time will tell on the life.. Hopefully it'll last longer than the original..

Would recommend to a friend?
Exact batteries I needed
January 26, 2017
by on January 26, 2017

I needed six new HC1221W batteries for my PurePower 2000 AC regenerator. I ordered on them on a Tuesday evening and the following Friday they arrived. Quick shipping, fresh batteries that were an exact match for what I needed, and a great price. I recommended Battery Mart to several friends, one of whom purchased six batteries for his PurePower 2000 from Battery Mart the following week. He is happy, too. I will shop Battery Mart again.

Would recommend to a friend?
Good Experience
September 26, 2016
by on September 26, 2016

It can be hard to find the right batteries for large items like a UPS, you get the right rating but sometimes it doesn't fit.... but everything was perfect with Battery Mart :)

Would recommend to a friend?
would buy item again from you
December 3, 2015
by on December 3, 2015

This battery was for my unit which controls my computers and printers if an electrical storm happens. Note When I opened the unit the battery had its description printed on it ---made it easier for me to order the right one for replacement..

Endicott NY
Would recommend to a friend?
Easy order, Good price, timely delivery
November 20, 2015
by on November 20, 2015

Just what I needed - approrpriate for the device.

Marti B
Elmira, NY
Would recommend to a friend?
July 10, 2015
by on July 10, 2015

Bought 2 of these to replace worn/dead batteries in an APC back-ups. They fit perfect and worked great.

Would recommend to a friend?