ADT 4520638 Security Alarm System Battery 12v 33Ah
OSI Batteries is your One Source for replacement ADT Alarm System backup batteries. Vision 6FM33U1 is a Sealed Lead Acid that fits ADT 4520638 model security alarm systems.
We recommend checking your existing battery for size and specifications prior to ordering as manufacturers may change requirements without notice.
We recommend checking your existing battery for size and specifications prior to ordering as manufacturers may change requirements without notice.
| Chemistry: | Sealed Lead Acid |
| Nominal Voltage: | 12v |
| Nominal Capacity: | 33Ah |
| Dimensions (In.): | 7.68 x 5.12 x 6.10 |
| Terminals: | NB |
| Weight (lbs): | 22.5 |
| Warranty: | 12 months |
| Condition: | Brand New |
| Notes: | 10 Years Design Life |
Reviews
We're currently collecting product reviews for this item. In the meantime, here are some reviews from our past customers sharing their overall shopping experience.
4.7
Out of 5.0
Overall Rating
96%
of customers that buyfrom this merchant give
them a 4 or 5-Star rating.
August 20, 2026 by William C. (TN, US)
“Easy and straight forward.”
August 20, 2026 by BobD (NY, US)
“Finding needed product and subsequent checkout process went very smooth.”
August 17, 2026 by Alan D. (MI, US)
“I was able to retrieve my order from 2024 and confirm the right product. Thanks.”
