Not enough glue inside the wood halves! The “lead” comes loose and slides up inside when you try to make a mark.The price is just right and the product work in different background colors.I am a welder/fabricator and have tried out a number of making utensils for use in the shop including scribes, soapstone, Grease pencils, sharpies, and more.The silver pencil and the mechanical version are my favorites. They both make a very clean and fine line on mill scale and clean metal. It isn't as visible when the metal is ground or polished, but that is to be expected.Here are some pros and cons as well as a comparison to the mechanical silver streak pencil.Pros:Crisp lineGoes on smoothCan be sharpened in a pencil sharpener or with a knifeCan be wiped off if you make a mistake but still stays putSlightly harder "lead" than the mechanical versionCons:The red pencil is only really visible on shiny metalAs it gets shorter it becomes harder to pull out of a work pouch pen holder.Inconvenient to go to a sharpener or sharpen by handI use both this and the mechanical version. I find this is most useful in a workshop where you can use a sharpener or stop to use your knife.The mechanical version functions better when in a larger work environment where you are constantly working in different areas and don't necessarily have time to stop and sharpen your pencil.Both have their merits and i hope my review was helpful.I will definitely but again.Some reviewers have said that the silver doesn't show up on shiny metal. It is t meant to be used on clean shiny metal. It's for darkened metals (ex: mill scale, light oxidation, light rust etc).Silver can't be easily seen on shiny surfaces. Come on, give me a break.If you're going to mark a shiny clean piece of metal, use a good ol number two pencil and be done with it.The red is good for lighter colors where the silver doesn't show up l, but since I use a number two pencil, I don't use the red much.It's a good pencil and for what you're paying, you can't complain.It does what it says it does and it does it well. Nothing to it.the pencil lead broke all the time, and it is a pain to sharpen, but i used it often when i was able to not break the lead.i used light pressure and it still broke a lot, the lead is just soft and maybe it was broken iin the manufacturing process and i just got the results when i tried to use itMy boyfriend has been welding for numerous years and actually never heard of these. I was pretty proud of myself finding a little present for someone who always seems to have everything! Anyway, he used them and really likes them. I'll state the obvious that the silver pencil doesn't show up on aluminum or any other shiny metals. He mentioned that the red ones were really useful but honestly saw no use for the silver in welding (since even an older metal would be ground down to fresh metal before welding).The silver pencil really does great for making fine lines on fresh hot-rolled steel. The red one is great for aluminum. They'll never replace soapstone for working in the weather, but for my shop, they serve very well! My only complaint is that the leads are really fine versions of grease pencil and so aren't tough enough to stand being dropped. Otherwise, they're great for fine layouts.The red one is good for precision cuts and marks shows well on all but oily surfaces. The silver doesn't write if there is any oil on the workpiece, if the piece is clean it's invisible. It does decent on some smooth millscale though. Also requires constant sharpening because of the soft "lead". If you're a welder just stick to soapstone, which is 1000x more practical for daily use. The pencils are useful for parts and fab work, but not being able to transport it without losing it from my soapstone pocket has resulted in it spending all its time in my locker at work.With all the great reviews I was thinking these were gonna be a game changer,but I’m going back to soap stone. I figured the silver wouldn’t be ideal on clean metal (it’s not) so I got the red as well thinking it’d show up great,but it doesn’t. Maybe it’s my lighting or something,but they don’t perform how I expected. I’ll be trying them on different surfaces,but they aren’t what I want for most of my work. Not calling them garbage,just not right for me.I bought some of these and recently brought some knock offs I'd assume of these from the local hardware. The hardware ones are made in Mexico and the markal are USA. You'd expect the USA ones to be the superior pencils but that's not the case. After 1 use the center crayon is sliding out of the wood. At the price I paid I wasn't expecting this kind of thing. I guess I'll try gluing it in before throwing it in the trash.Garbage. I sharpened all of them down to nothing and the lead was broken all the way through on all of them. And now of course I can't return them because they're gone lol. I had to sharpen them in order to find they were no good. Then I bought the ones from Grainger and it's not the same product at all everything about them is different. Grainger has the real ones and they're very good qualityThese are hands down the best pencils for any type of metal work. Once you sharpen it.. it leaves a clean nice sharp line. Also if your doing any torch cutting the pencil mark will not burn out. In my years of experience this is the best pencil I’ve ever used. My suggestion to everyone is buy the 12 pack because they go quicklyI would not recomend this product to anyone does not work very well on steel. is far to faint to see. the red show a bit better, but a slimline sharpy pen is a much better choice and cheaper