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.
October 30, 2026 by Luke S. (ID, US)
“great, no complaints”
Merchant Choice
had the exact part number displayed with the product
Product choice
Epson manual
October 28, 2026 by Michael M. (WA, US)
“OSI has been a great asset for replacement Biomed batteries. Never an issue start to delivery. Thank you!”
October 20, 2026 by Jacob W. (TN, US)
“Very easy website to navigate and I appreciate that!”
Merchant Choice
Chat gpt recommended you for this older SL-20x stream light flashlight replacement battery.
Product choice
Price was really responsible, actually one of the cheapest I’ve seen not on eBay and in the US. Shopping for something and needing it in a reasonable time frame I always look for an address in the USA and I like supporting companies that still sell things like this in the state. Thank you for still supporting this flashlight!!
