Batteries D34M BLUETOP® Dual Purpose Boat and RV Sealed AGM Battery | High Performance Deep Cycle and Starting Battery, 750 CCA, Dual Terminal, Maintenance Free, Versatile Mounting

This is the ONLY battery you'll ever see in my boat !! Holds a charge a long time and can go the distance running lights and sound system for hours then still crank the boat up like a boss. I keep a tender on it all winter, then in Spring it fires my boat right up like it was brand new !!

I am like a lot of people wanting to save a few bucks. Unfortunately when you buy economy batteries you often lose money in the long run. This was the case for me so this time I went with a recognized industry leader. Optima batteries are top of the line and the difference in power and run time increase with these batteries is amazing. One word of caution. These are AGM batteries and they must be charged with a charger programmed for AGM batteries. If you use the wrong charger it could damage or destroy the charger and/or the batteries. Fortunately the onboard charger in my bassboat is designed to charge all types of batteries and a simple change of a screw in sensor ensures I will have these batteries in service for a very long time. When these batteries were delivered one of them was upside down. You can mount AGM batteries at any angle because there is no possibility of losing acid from the battery. The acid is soaked into fiberglass pads inside the battery. They were fully charged when I received them and I fished 2 long days with them before charging for the first time. I would highly recommed these batteries for any marine application. For the fishermen who have not used AGM battrries a word of caution. AGM batteries provide full power until they are dead. Most batteries will provide less and less power as the charge is depleted. That is a positive thing. Just know that when your battery loses its charge you have no notice. I charge every time I go fishing so I dont see this as a problem..

I bought this battery a bit over 1 year ago (on May 2023). Even after completely charging the battery on an OPTIMA charger, the battery would barely crank over a 20 hp outboard motor. I should have tried to return the battery then, but it still worked (barely), and I needed it for the boat. In Nov 2023 the battery was placed on an OPTIMA charger over the off season. Once again, this spring, the battery is still weak. The battery is not much better than the OPTIMA battery I replaced which I used for 9 years! Very disappointed and I will not be purchasing OPTIMA batteries again. UPDATE: I called customer service and explained the problem, and they will honor the warranty. Following the phone conversation, I got an email that said: We will need a picture of your proof of purchase and a picture of the bar code on the side of the battery Put your case # in the subject line and email to amazonwarranty@optimabatteries.com I have yet to send in the info, but it seems like I will be able to get a replacement (I'll update here if I do not) So, great Optima customer service! (I knocked off one star as I did receive a faulty battery) Last update: Replacement battery just arrived!! Added back a star

It has been 10 years and 2 months now since we bought this battery. Put it on the boat every spring and took it off every fall. We’ve kept it on a trickle charger over the winter each year. Last week was the first time it didn’t start right up. Still not sure if it’s completely dead, but to go for over 10 years on a boat is pretty darn impressive. The other cool thing about this battery is that you can use a paddle board inflator without the boat being running. Not many boat batteries can do that! Love this battery and hopefully we can keep it going for a bit longer. If not, I’ll buy this same one again.

I have used Optima batteries on my boat for several years. The batteries deliver good performance and I received 4 years of service out of the last D34M. I ordered a new Optima from Amazon as they offered the best price however the battery arrived damaged as it obviously had fallen out of the bottom of the box. The box was too big for the product, very lightweight, and only had paper wrapped around the battery for padding. UPS attempted to put the battery back in the box and added more packing tape but the battery had been damaged where it hit the ground. Amazon customer service was great in resolving the issue quickly (and at 9:00 pm) by sending me a replacement. Guess what happened to the replacement? Yep, it too was packaged the same (after I specifically asked for better packaging) and had fallen through the bottom of the box, cracking the case. UPS also retaped the box and delivered the second damaged battery. Amazon customer service was willing to send me a third battery but I asked for, and received a refund instead. Now I have two damaged batteries I need to dispose of (the batteries cannot be returned to Amazon as they are considered hazmat).....

With the price of batteries these days , I hated to spend the money, but this battery is lighter than most. Making easier to take in and out of my boat. High quality and long lasting charge.

Just bought in July 2024 to replace a dead AGM. Battery seems to hold a 12.4v charge when I do not have the battery charger on the boat run. I drained the charge in 2 weeks with just the marine radio idle - not on - which was surprising. But, did let me know the Guest 10 amp charger was toast ( it lasted a surprising 20 years). Running two Humminbird Helix units, starts a Yamaha 150 hp 4-stroke and all boat accessories. Have hit it pretty hard with say 6 hours on the sonar units and so far so good. Will report back, but seems like a good battery and alternative to the newer lithium batteries.

I read a lot of details on the Optima battery line before purchasing this one back in February 2015 for my old CJ-7. I've had a lot of bad battery experiences through life and this time I decided I was going to pay the extra and get a high quality battery. I wanted a good mix of cranking power and long reserve for camping situations and after seeing so many good posts in various Jeep forums I went with an Optima BlueTop. I can say this BlueTop battery has been worth every penny so far and I expect to get well more than my money's worth out of it. This battery easily spins my 4.2L endlessly anytime I'm doing work on it without ever seeming to indicate it's had any drain at all. I've jumped numerous other vehicles off, run lights all night camping, etc. and never noticed the drain. I even accidentally let the battery drain itself dead from a small wiring short. It was left completely drained and dead for 4 full months and all I had to do was run a slow trickle charge for a couple of days and it charged right up and churns like new still with no issue.

Great battery no complaints

Use this batterie on my boat working great

House battery for sailboat. Perfect fit. Delivered on time.

Battery does not hold charge. I had Optima batteries before, I only use Optima batteries for my cars and trucks but this time I'm having a bad experience. maybe its cause I ought it on amazon and batteries are old. I had good experience with Amazon too just waiting for their response. Will review again. buy from your local store these guys are not covered under warranty i'm stuck with two batteries and lost $800 usd very sad

Exceptional product