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Penn Slammer IV Review: Strong and Steady Wins The Race  

Penn Slammer IV Review: Strong and Steady Wins The Race  

Sometimes in life, we’re forced to decide between the “jack of all trades” option and the “one and done” option. When it comes to fishing reels, I find that a lot of reels fit this description. Some do a lot of things but none of them very well, while others only do one thing and do it very well. 

In this Penn Slammer IV review, you’re going to see a reel that focuses on being a brute force saltwater reel and not much else. 

Bottom Line Up Front:

The Penn Slammer IV is a powerful, durable, and gutsy saltwater reel designed to handle serious abuse from salt spray and hard-fighting fish. It’s priced affordably to allow newbie anglers to access saltwater fishing with the right gear. 

About The Penn Slammer IV 

The Penn Slammer line of reels is known for being a sturdy and powerful set of saltwater spinning reels. With the addition of the Dura-Drag system and completely sealed body, they are one of the most popular saltwater reels in this price range. 

Penn introduced the Slammer III in 2016 and it won best new product at iCast. That reel lacked a lot of the main features you’re going to see in the Slammer IV but it was still considered the “workhorse of the event.” 

The manufacturer has a long history of excellence in the fishing world and they are a brand I’ve always respected. I may not have used Penn reels like I did Shimano but I still have many years of experience wetting lines with my Penn Pursuit reel. 

Penn Slammer IV
Photo by Coty Perry

Specifications Model Chart Comparison 

Normally, this is where I would include a chart to help break down the various models of whatever reel I’m reviewing but in this case, the Penn Slammer IV has 13 different reel sizes which is a plus in itself. But, it makes it hard to put together a chart that large. 

You can find a full model comparison here


  • Affordable for what you get 
  • Exceptional waterproofing increases the life of the reel
  • Very high max drag ratings
  • All brass CNC gearing promotes durability 


  • Heavy
  • Lacking balance

Where to buy:

Key Features of the Penn Slammer IV 

The point of this Penn Slammer IV review is to help you understand the features of this saltwater reel and how they impact your fishing. While this reel has a lot of flashy and interesting components, they’re all useless if you don’t know how to apply them. 

Full Metal Body and Sideplate 

Penn Slammer IV Spinning Reels
Photo by Coty Perry

The point of having a full metal body and side plate is to help keep everything aligned properly when the reel is under pressure. When there is plastic or cheaper materials used, the reel will flex which can mess up the pinion and gears inside resulting in a shorter lifespan and reduced smoothness over time. 

CNC Gearing 

This is Penn’s flagship feature on all their reels and it’s something that sets them apart from the competition. Their CNC gearing technology makes all components of the gearbox out of brass and since they use a CNC machining process it ensures precision. This results in enhanced cranking power which is especially important when dealing with saltwater. 

IPX6 Sealed Body 

IPX6 is the rating this reel gets for its sealed design to prevent saltwater from accessing the internal components like bearings and gears. This is important because of salt spray and water coming off the line as it respools. It’s crucial that you have a well-sealed reel to prevent water from accessing and rusting everything out. Penn offers some of the best technology in this regard.  

Dura-Drag System 

The Penn Slammer III introduced the new Penn Dura-Drag system and they brought it back for the IV model as well. This is proprietary technology that you’ll only find on higher-end Penn reels. The manufacturer coats all the washers with something called Phenolic to help make the drag smoother and enhance the overall durability. This is part of the reason why the drag rating is so high even on lower model reels. 

8+1 Stainless Steel Bearings 

The jury is still debating whether or not more bearings equals enhanced performance and to be honest, it’s very hard to tell the difference but it’s still a feature. The Penn Slammer IV comes with eight stainless steel bearings and one anti-reverse bearing. 

Hydrophobic Line Roller Bearings

This is an interesting feature that I’ve honestly never heard of so I had to dig deep to find information on it. The bearings are coated with a special lubricant that makes them resistant to water damage. So, in addition to incredible sealing, if any water does penetrate inside of the spool, the bearings can resist it. 

Oversized Knob with Backup EVA Handle 

Penn Slammer IV Spinning Reels
Photo by Coty Perry

The knob on the Penn Slammer IV is ridiculous and as soon as you put this reel in your hand, you realize that you’ve got a piece of equipment that is designed to pack a punch. It also comes with a smaller backup EVA handle if you’re finessing smaller fish in canals or inland lakes and ponds. 

Buying Criteria: Choosing Your Spinning Reel 

Understanding the features of the reel is great but it’s also important to know how to choose a reel based on that. One of the most important things I’ve learned from testing over 25 reels is not to think too hard about it. 

All of the reels you’ll find in this price range are going to perform well, hold up for a long time, and likely meet your expectations. Only people with experience tearing down reels would be able to tell the difference between some of these features. 

Anyway, let’s get into it. 


Would you look at that? Features are the first thing. You want to look at the features of a reel and see what it brings to the table. A lot of what you read can be nonsense that won’t impact your ability to catch fish. 

For that reason alone, I only discussed the various features that I think will have an impact on the performance of the reel in a way that will make catching fish easier and more enjoyable for you. 

Be sure to go for reels that offer bang for your buck. If you’re paying for a premium reel, you should expect that reel to be loaded with premium features. 


The brand is so important because it plays a major role in the quality of the reel you get and the customer service you experience if you have an issue. Penn has been around since the 1930s, they have a strong reputation, they’re not going to let you down. 

This is why I strongly recommend shopping the major brands like Penn, Shimano, Daiwa, and Pflueger. When you purchase a reel from these brands, you know you’re getting something of quality and not a cheaply made product from a company that’s just reselling gear. 

Gear Ratio 

The gear ratio is something that a lot of anglers struggle to understand but it’s very important in saltwater fishing. Gear ratio refers to how many revolutions the spool takes for each crank on the reel. 

In the case of the SLAIV4500, it has a 6.2:1 gear ratio. This means that each time you turn that handle, the spool will spin 6.2 times. 

Why does that matter? A higher gear ratio means you won’t have to crank as much to get the fish back to the boat, this works great for smaller fish because they don’t put up as much of a fight and you won’t be as fatigued if you’re reeling in a lot of fish. 

When it comes to saltwater, a lower gear ratio can be better because it’ll put less pressure on the drag and allow the fish to tire itself out without overworking the reel.


Penn Slammer IV Spinning Reels
Photo by Coty Perry

I mentioned the weight and balance of the Penn Slammer IV to be a con and I still believe that it is. It’s a heavy reel, no doubt about that. But, sometimes reels that are designed to pack a punch will be heavy. The biggest problem I have doesn’t come necessarily from the weight but the balance of the reel. 

I find that the reel is set so far from the blank that it makes it feel heavier than it is. Now you have a reel in the 10-12 oz range and it sits on the rod like a lump and pulls it down because it’s so far away from the blank. I’d like to see them center it a little closer and shorten the length of the foot. 


Comparing the reel to some similar alternatives is a great way to get an idea of how the features stack up against other options. 

Shimano Stradic FL 

The Stradic FL is one of my favorite reels from my favorite brand. This reel is more affordable than the Penn Slammer IV and it offers a lot of the same features while also being much lighter. That said, it doesn’t have the guts of the Slammer. The drag racing is a lot lower and it’s not as well equipped to handle the salt. 

I’d say if you’re looking for something a little more affordable and more versatile for use in canals, lakes, and rivers, you’ll want to go with the Stradic FL. If you’re strictly focused on offshore saltwater fishing then you’ll want to stick with the Slammer. 

Continue reading our complete Stradic FL Review.

Penn Battle II 

Penn Battle II

The Penn Battle II would be considered a “budget” reel from Penn. It’s priced at around $100 so it’s a third of the price of the Slammer but you get a third of the features as you would expect. They’ve got a lot of great oversized saltwater models and it comes with the full metal sealed body and all the proprietary Penn technology. 

One feature I love about the Battle that you don’t see in a lot of the newer models is the Superline spool. It comes with line capacity rings to give you an idea of how many lines you have remaining on the spool. This is a great feature for offshore fishing as well. If budget is the main issue for you, the Penn Battle II is a great alternative. 


Here are some of the most frequently asked questions about the Penn Slammer IV. 

Question: What is the biggest Penn spinning reel?

Answer: There is a 10500 model size of the new Penn Spinfisher V. It’s designed for heavy offshore fishing and can hold its own in any situation.

Question: Is Penn a good fishing brand?

Answer: Penn is a top 5 fishing brand across the world and they hold records and top rankings in various fishing tournaments.

Question: Are Penn reels good for saltwater?

Answer: There are several Penn reels designed specifically to prevent saltwater corrosion with the Pursuit, Battle, Slammer, and Spinfisher being the most popular options.

Final Thoughts 

To wrap it up, the Penn Slammer IV is one of the best saltwater reels in its price range, hands down. It’s built to last and it’s capable of taking quite a bit of abuse, what more could you ask for? 

I recommend taking a look at some of the product pages, reading a little more about it, and then taking a dive and picking it up for yourself. Good luck out there!