What's new
  • Welcome back Guest!
    If you have been away from our site you may have to request a new password. Simply click on the link for "lost" password in the log in page.
    Thank you.
  • Guest
    The BST is now open, please note the changes in our guidelines to address the recent fraudulent activity. Ensure you read the guidelines prior to creating a sale thread in the Buy-Sell-Trade forum with special attention to the new photo and payment requirements.
    Thank you for your patience and understanding.

Newbie how to tell a Slim from a Fatboy Guide ( and other things )

While the more established members here will discuss about whether it's a Aristocrat #x or a Aristocrat #y because of the Patent Number or the Diamond Silo or the endcaps or the knurling........., it appears to me that the most readily available razors that newbies have issues with in telling apart is the Slim and the Fatboy.

So often on Ebay Auctions the description will state that the razor is a Fatboy when it's clearly a Slim. Whether this is a mistake by the seller or an attempt to cash in on the higher prices fetched because of the Fatboy recognition I'm not sure.

As a still relatively new newbie, to give something back to the forum I though I'd put this quick guide together. Hopefully this simple guide helps you more accurately pick the slims from the Fatboys. It's not a complete guide and doesn't cover things like the Fatboy bottom adjuster or the gold slim ( Aristocrat ) or the gold Fatboy ( Executive ) but hopefully helps you make a more educated "guess".

( Please note it's 2am and as an insomniac I can't sleep so if there's any errors here please point them out so I can rectify ( and it's also why the pics aren't the best ). I am NOT responsible for incorrect purchase made using this guide:001_tongu )

Here's my quick guide for telling the two units apart.

In all pictures the slim is on the left and the Fatboy on the Right.


If you're lucky enough to find a cased Slim or Fatboy then they're pretty easy to tell apart though beware, I've seen Slims in Fatboy cases and ( more rarely ) the other way around . In fact keep your eyes open because you see all sorts of razors in all sorts of cases that may or may not be a match. You can be bitten badly or you can also get some really nice buys ( this goes for all cases and all razors not just the two discussed here )

The slim case comes in a number of colours white, red , blue ( and maybe more ) and the backing "glitter" came in a number of colours as well.


While they're pretty similar , note that the Fatboy is slightly shorter than the Slim. Note that the TTO knob and the "body" of the razor handle on the slim is much longer. The Fatboy is thicker ( hence the name ) and the TTO knob is more obviously wider than the handle and has the smooth area above the knurling.

If you can't see the TTO knob , another way is to look at the Adjuster Knob. Most obviously the "grip" on the Fatboy knob has long vertical lines while the slim has a smaller knurled pattern. Also the adjuster on the slim has smooth ( where the numbers are ) , knurled, smooth while the Fatboy has smooth then knurled only ( does that make any sense ? )

Slim: 9 cm ( 3.5 inch )
Fatboy: 8.5 cm (3.35 inch )


Underneath the head of the razor you'll find a date code which consist of a letter on the LHS and a number on the RHS. From this we can tell the year and quarter in which the razor was manufactured.

Given that the Fatboys were manufacture before the Slim you'll see them with the ranges between D1 to G4.

Slims will have the markings of G1 to N4 so there was one year of crossover.

There's a full chart on the Wiki here: http://wiki.badgerandblade.com/index.php/US_Gillette_Dating_Information

Below is the Fatboy , note the G 2 underneath the Gillete logo, so manufactured second quarter of 1961 .

( This doesn't only apply to the slim and the Fatboy, most USA razors manufactured after 1950 will have these datings on them )


The Fatboy has a much higher domed head

( Note the differences between the knurling on the adjuster as mentioned above )


The Fatboy is fat and the Slim is slim....... :tongue_sm

Slim approx 71 gm ( 2.5 oz )
Fatboy approx 78 gm (2.8 oz )

Adjustable ?

While this probably won't help identify a razor a quick discussion about the adjustable component. Most often you'll see razors discussed in terms of "agressiveness". If you take for example the Super Speed family, they put this out in a Blue tip ( mild ), Silver tip ( Normal ) , Red Tip ( Aggressive ). With an adjustable razor you can change the "aggressiveness" all in one razor.

Notes On both the Slim and the Fatboy when you change the setting ( by turning the adjuster knob at the top between settings 1 and 9 ) you should open the doors, adjust your setting then close the doors. Common belief is that if you don't do this you may put undo stress on the system. In addition, once you've made a change tighten the TTO Knob and once you meet pressure you should turn it another 1/4 twist to lock it off.

What does the adjuster do ? On the LHS picture the adjuster on both unit is set to 1. On the RHS the unit is set to 9. Note the height of the "bars" in the silo. 1 raises the bars, 9 lowers the bars. Settings in between ... set the bars in between these two "extremes" :biggrin1:

The effect of this is that it changes the pressure on the actual blade and increases or decreases the gap between the razor edge and the safety bar.

So compare the blade distance setting on 1 on the LHS versus the setting on 9 on the RHS in the picture below.

In general the larger the gap between the razor and the guard, the more blade that is exposed and the more "agressive" the razor is.

Gee 9 razors in 1 :biggrin1:

General consensus seems to be that if you're new to DEing and have one of these, start at the 3 setting and practice your technique at this setting. Once you become more experienced you can start playing with the adjuster to find the right setting for you. Some people find their ideal setting and just leave it on that, others will use different settings for different passes.

Hoping that this helps. If it helps one person on the forum at least I'll feel like I've contributed something back to the forum .

BTW If you don't want to face the unknown factor of buying off Ebay in terms of model, the condition or the price, try using B&Bs own Buy/Sell/Trade ( BST ). Takes all the risk out of the purchasing :biggrin1:
Last edited:


Moderator Emeritus
Great work, fidjit! Very nice descriptions, explanations and pics!

I'd like to add that, for me, when I see pics of Slims/Fatboys, for example, on ebay, it's usually a single razor, and not a Slim and Fatboy side by side where the differences are a little easier to see. And the pics aren't always great closeups like yours. Sometimes you can't even make out the detail of the knurling very well.

Maybe I've trained my eye, but it seems to be pretty easy now, for me, to see if it's a Slim or Fatboy by looking for the wider, angled ring at the bottom of the Adjuster Knob. If it's there, it's a Slim. If not, it's a Fatboy. That just really stands out for me.

Again, great post, and a big "+1" on buying here on B/S/T where it's safe. I've noticed on ebay the approach seems more likely to be to post pictures that show the "best side" of razors, and just not show or describe the side or parts that aren't as nice. I won't say ebay sellers are deceptive, I just prefer the very upfront approach on B/S/T where sellers seem to really "bend over backwards" to make sure you know of anything that is less than perfect with an item being sold or traded. :cool:
This is a great idea. When I first started, I really had no clue between several of the "basic" razors. Guido was kind enough to help me with my juvenile questions without any ridicule, but a thread like this would have been nice.


Moderator Emeritus
Very nice post. I, too, am convinced that some of the mislabeling of so-called fatboys on ebay is less than innocent. Buyer beware!
Nice work, fidgit. Quite a complete comparison. Case switching and wrong identification is one of my pet peeves as well.

It's a little trickier with the adjustable aristocrats and executives. To tell a fatboy from an executive, look for the slim style knurling and the gold plating that should be on an executive. The adjustable executive is identical to the fatboy except for its gold plating and it's knurling, which is like the knurling of a slim and not that of a fatboy (a checker pattern as opposed to the long lines). To tell an adjustable executive from an adjustable aristocrat, use the rest of the guide above. I've made the mistakes, so I thought I'd help out and keep others from making mistakes.
Hope that hasn't already come up in the thread. :biggrin:
Thanks for all the positive feedback guys.

I've done some minor edits this morning including grammar ( which still isn't very good but better than a 2am effort :001_tongu )

While a noob myself, I'd really like to assist the newer noobs :lol: and I've seen so many useful posts disappear into oblivion as they're replaced by later posts on the forums.

Not sure what the protocol is here but is this the sort of thing that should be in the Wiki ?????

Can I just go and post it there or does it have to be approved ????
Last edited:
I've just put a link to this post under the "Identifying your DE razor" in the Wiki and put a link in my sig. Hopefully that's all right.

Hopefully it may stay (at least semi ) alive and help some of the Newbies out :001_smile.

Nothing like a bit of blatant self promotion :tongue_sm
Nice work Fidjit. I'm pretty good with Fatboys and Slims, but I'll definitely refer to this if I ever look at buying an Aristocrat / Executive.
Maybe the mods could add a link to this thread in the Sticky at the top of the Safety Razors forum?
This is a superlative post. As one who very recently made the mistake of incorrectly calling a "Slim" a "Fat Boy", I appreicate the time and effort you made to put this together. Thanks!
Great information for me, a newbie that just got a fatboy.

Opinions - slim or fatboy?
Question - When adjusting between passes, more or less aggressive with certain strokes or further into the job?

Thanks again!
This is a great idea. When I first started, I really had no clue between several of the "basic" razors. Guido was kind enough to help me with my juvenile questions without any ridicule, but a thread like this would have been nice.
Wow! Am I feeling old. Here you are with 4,444 posts and saying I was helping you when you were a newbie? :eek:
Hey fidjit! Great informative post! I even learned a few things myself. Thanks for taking the time to put this together. It is superlative!:smile:
Top Bottom