Brother Profile 500 is a metal flatbed knitting machine with 200 needles 4.5 mm apart. It is a standard gauge machine with only basic patterning capabilities. Additionally, the end-caps are not plastic (like later Brother knitting machines) but metal, which makes them more robust and less prone to breaking (especially during shipment and transport) and UV-exposure damage.
I could not find definite information on when it was made and released to the market. But here are some ideas: it is very similar to the 4-push button Brother Profile 551 but the row counter is more advanced (like the first 8-pushbutton mode Brother KH552). The tension mast is also a bit more advanced. So, I suspect the Brother Profile 500 is a bit less vintage and was on the market in the 1960s.
By looking at the original cardboard package, we can say that Brother KH500 came to the market definitely after Brother KH551 (its more advanced 4-push button counterpart). The image on the box shows a model with a 4-pushbutton, a ratchet tool, and a slip-on vintage row counter.
However, all other assesories are the same.
The carriage has tuck, plain, and part buttons. The cam levers have only two positions: I and II (unlike more advanced machines that also have III). Part buttons are used for fair-isle, tuck and part (the cam levers should be in position I). For holding and/or partial knitting set the cam levers in II positions,
The model does not come with a lid. But this is actually what makes the whole setup lightweight, especially for people with insufficient upper body strength. All large assesories (mast, cast-on combs) fit inside the cardboard box.
The handle screws onto the carriage.
And fits nicely inside the tools box with all other assesories when not in use. And if you are lucky, your toolbox will come with a lid – then you can put the whole setup onto the main bed for storage and transport.
Needles for this and its other vintage counterparts are very unique: they have a concaveness near the needle butt. These needles can only be purchased on the used market. I have them in my store as well.
Table clamps are S-shaped, unlike later Brother knitting machine models. The head of the “S” is smaller than for similar ribber clamps.
The retaining bar needs a sponge strip, which needs to be replaced every 6-12 months depending on how often the machine is used and how vigorously it is oiled. The retaining bar is 41 x 0.5 inch and can be purchased new.
I also could not find any information on whether any major assesories can be fitted into this machine. However, because of the similarity of Brother Profile 500 with other Brother machines from the same era, I suspect that ribber KR551 might fit to convert Brother Profile 500 to a double bed for more advanced patterns. There is a chance that ribber KR580 can also fit this machine. But if you are a knitter who is attracted to this machine because of its ONLY manual capabilities, you are very likely a knitter who likes hand-manipulating stitches. So, you will probably want to machine-knit your ribbing by hand instead of spending all that precious time testing which ribber fits and adjusting that ribber properly (because trust me – there are no instructions on how to fit a ribber to Brother Profile 500). Or maybe you are just a very determined machine-knitter… If so – email me so we can meet each other 
I personally had the honor to work on two Brother Profile 500 machines (video and blog entries are available). Both worked great and both had their own characters despite being so similar. This is actually true for any knitting machine: knitting machines of the same model very easily can behave differently (just because). The same machine will behave differently depending on the operator, yarn, and even weather (sometimes humidity helps with eliminating the static). So, I can first-hand judge about pros and cons of this machine and here they are:
Pros and Cons of Brother Profile 500 knitting machines:
PROS:
(+) The bed is narrow which makes the overall setup compact, very light, and easy to handle.
(+) The carriage is very easy to slide across the bed
(+) Excellent for beginners and those who transition from hand-knitting to machine-knitting.
(+) Relatively easy to deep clean (even from rust) – all parts are mechanical and straightforward, so it is easy to assemble and disassemble if deep cleaning is needed
(+) Nice green color, which makes it stand out.
(+) Might be compatible with several ribber models and probably with KL111 knit leader (available in my store) but I personally did not have a chance to test it.
(+) The row counter is a more recent model, which can be purchased on the new market if the row counter is misplaced or lost or your machine did not come with one.
(+) A significant advantage of this machine relative to its later counterparts (some pushbutton, and most punchcard and electronic knitting machines) is all metal parts (with the exception of some small knobs and levers). Thus, no UV damage and discoloration to the main parts of the machine (unlike later models, in which UV damage, aging and the resulting discoloration of carriage plastic panels, end-caps and top panels can be quite significant).
CONS:
(-) Pretty basic model and offers only manual manipulations of stitches/needles to achieve any sort of patterning.
(-) Unique needles that can only be purchased on a used marked
(-) No lid, which might make this machine more prone to UV and damage from the elements, dirt, etc. However, the absence of a lid makes the whole setup lighter. I simply cover machines with a curtain to prevent damage and getting dirty.
If you are looking for this model, it might be available in my store. Some might find the machine too simple – yes, it has only limited patterning capabilities. However, with manual needle selection and yarn manipulation, the possibilities are endless, which is kind of a big plus to artists and hand-knitters who just transitioned to machine knitting and not ready yet to give up the feeling of satisfaction of hand-manipulating the stitches.
Happy Knitting!
