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MK Battery M40 Sealed GEL Pair Battery

Model: M40-12 SLD G |

List Price: $440.00

Save: 33%

Our Price: $296.00

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This example payment is the amount of equal monthly payments on a loan to finance the purchase based on the listed product price of $13.66 assuming a 24 month term and a 9.99% APR. Your terms may vary and are subject to credit approval. Rates range from 5.99% to 29.99% APR. Bread® loans are made by Cross River Bank, a New Jersey Chartered Bank, Member FDIC.
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  • Deep Cycle Premium sealed batteries capable of up to 500 cycles that are fully laboratory tested.
  • Gelled/Suspended Electrolyte No liquid of any kind; battery is completely sealed. Safe in any position.
  • Maintenance Free Water is never added; low liability
  • Travel & Ship Easily MK batteries are F.A.A, IATA, and UPS approved.

Benefits of an Advanced Gel/Sealed Battery

  • 4 Battery technology has changed tremendously in just the past few years. In fact, size-for-size, MK's advanced gel/sealed batteries deliver more power and more consistent performance than other types and brands of mobility batteries.
  • Last longer than comparable wet lead/acid and marine batteries.
  • Are approved for airline and public transportation.
  • Do not need to be fully discharged before recharging.
  • Do not develop a "memory" that limits their recharging.
  • Do not need to be recharged with lower amps than wet lead/acid batteries.
  • Will not automatically discharge if put on concrete.


GEL Battery

  • Capacity at 5hr RATE  34AH
  • Capacity at 20hr RATE 40AH
  • Capacity at 100hr RATE 48AH


  • Weight: 32 lbs each
  • Length: 7.76"
  • Width:   6.62"
  • Height:  6.87"

GEL vs. AGM Sealed Batteries

AGM (absorbed glass mat) is a special design glass mat designed to wick the battery electrolyte between the battery plates. AGM batteries contain only enough liquid to keep the mat wet with the electrolyte and if the battery is broken no free liquid is available to leak out.

Gel Cell batteries contain a silica type gel that the battery electrolyte is suspended in, this thick paste like material allows electrons to flow between plates but will not leak from the battery if the case is broken.

More often than not an AGM Batteries are mistakenly identified as a Gel Cell Batteries. Both batteries have similar traits; such as being non spillable, deep cycle, may be mounted in any position, low self discharge, safe for use in limited ventilation areas, and may be transported via Air or Ground safely without special handling.

AGM Batteries outsell Gel Cell by at least a 100 to 1. AGM is preferred when a high burst of amps may be required. In most cases recharge can be accomplished by using a good quality standard battery charger or engine alternator. The life expectancy; measured as cycle life or years remains excellent in most AGM batteries if the batteries are not discharged more than 60% between recharge.

Gel Cell Batteries are typically a bit more costly and do not offer the same power capacity as do the same physical size AGM battery. The Gel Cell excels in slow discharge rates and slightly higher ambient operating temperatures. One big issue with Gel Batteries that must be addressing is the CHARGE PROFILE. Gel Cell Batteries must be recharged correctly or the battery will suffer premature failure. The battery charger being used to recharge the battery(s) must be designed or adjustable for Gel Cell Batteries. If you are using an alternator to recharge a true Gel Cell a special regulator must be installed.

If you are unsure which battery or charger is best for your application, please call or email our tech people for help making the correct selection.






A battery will be replaced with a free equivalent at any of our dealers if it fails due to defects in
materials or workmanship within thirteen (13) months from date of initial installation only. A battery
used in a mobility application rated lower than 20 amp hours will be replaced with a free equivalent at
any of our dealers if it fails due to defects in materials or workmanship within six (6) months from date
of installation. Proof of date of purchase/installation required for all claims. Qualified MK Battery
distributors are authorized to execute this warranty; however, they must call MK Battery (800-372-
9253), for shipment of replacement or credit prior to disposal of the defective product. Normally, return
to MK Battery is not required however MK Battery reserves the right to require return and the method of
shipment. Upon receipt of the defective battery, MK Battery will process the claim and reimburse for
any direct freight costs as authorized by MK Battery.

This warranty does not cover failures in service due to the following conditions:
1. Unauthorized modifications or alternations to the products.
2. Negligence, accident, abuse, misuses including improper jump starting, or improper, unsuitable or
abnormal storage of the products.
3. Improperly installed or applied batteries. Improperly charged (either under or over) batteries.
Opening of batteries that are designed and intended in use as sealed products.
4. Physical damage due to acts of nature or man which stress products beyond design limits or other
undesirable influences.
5. Normal “wear and tear”.

MK Battery considers AGM batteries to be suitable for light duty mobility equipment only. AGM batteries
used in more robust applications such as complex rehab mobility devices, where daily deep discharges are
the norm, may void the warranty.

Any storage of batteries shall be at an ambient temperature of 77°F or less and user shall give a freshening
charge to all batteries every six months.

MK Battery shall not be liable to purchaser/distributor, or to any other person, either directly or by way
of indemnification, for consequential, incidental, special or direct damages, whether the claim for any
such damages is based on warranty, tort, contract, or otherwise.


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Our Price: $296.00
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Total Product Price: $296.00
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Customer Reviews  - 1 Review(s)

Excellent Web-site and Customer Service

The web-site is easy to navigate and find what your looking for. Before the sale customer service was very helpful.

Review by : Bill
Reviewed on : 4/30/2018

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