# Is this existing library component the one I want? **URL:** \ **Category:** Help\ **Created:** [July 16, 2023, 11:06am UTC](https://librepcb.discourse.group/t/is-this-existing-library-component-the-one-i-want/560 "2023-07-16T11:06:45Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![4Springs](https://avatars.discourse-cdn.com/v4/letter/4/ee59a6/32.png) [@4Springs](https://librepcb.discourse.group/u/4Springs)\ **Post date:** [July 16, 2023, 11:06am UTC](https://librepcb.discourse.group/t/is-this-existing-library-component-the-one-i-want/560/1 "2023-07-16T11:06:45Z")
I’m looking through the libraries to see if it has the MOSFET that I’m after. I find that it does have some MOSFETs - are they the same? I found one with the correct symbol and the correct package, but it is a different part number. I’ll use it if the pin numbers the same, but how do I tell? I tried adding the component and looking at the properties (I’m in the Schematic Editor). Here’s what I see: ![image](https://global.discourse-cdn.com/free1/uploads/librepcb1/original/1X/797975ce5ffe0d9633e6519432f122ef99edb0bb.png) I’ve created library components before, and I want to see the screen that matches the schematic labels with the pin numbers on the component. It looks like I should be able to click on the underlined text next to ‘Component:’. But that doesn’t do anything. Is there a way I can tell the pin numbers of the physical package for this library component? ---
**Author:** ![ubruhin](https://avatars.discourse-cdn.com/v4/letter/u/c89c15/32.png) [@ubruhin](https://librepcb.discourse.group/u/ubruhin)\ **Post date:** [July 16, 2023, 11:31am UTC](https://librepcb.discourse.group/t/is-this-existing-library-component-the-one-i-want/560/2 "2023-07-16T11:31:47Z")
Hi, In the schematic editor, pad numbers are currently not yet visible (they will be visible in the next release). The only way to check it within a project is to connect the mosfet in the schematic, then add it to the board and check the tooltip of the footprint pads - they show the net they are connected to. But I think currently the quickest way is to type “SSM3K329R” into DIgiKey, download its datasheet and check the pinout there 🙈 Anyway, I’d recommend to create a device for your desired Mosfet. Since there exists already one with the correct package, you can just duplicate it this way: ![image](https://global.discourse-cdn.com/free1/uploads/librepcb1/original/1X/c71e6a299010a53a2bc1c881d9a7ce410f8b9739.png) Afterwards you’ll see the pinout in the device editor. Since this whole process takes just a minute and ensures you’ll have the correct device in your schematic, I’d always go this way. ---
**Author:** ![4Springs](https://avatars.discourse-cdn.com/v4/letter/4/ee59a6/32.png) [@4Springs](https://librepcb.discourse.group/u/4Springs)\ **Post date:** [July 17, 2023, 10:09am UTC](https://librepcb.discourse.group/t/is-this-existing-library-component-the-one-i-want/560/3 "2023-07-17T10:09:20Z")
Thanks, I didn’t know about the ‘Copy from existing element’ function. Irritatingly though, when doing this step there is no search function. So I need to know the Device number of the component I want to copy. So I need to go and add a component to get the search function (MOSFET), find the one I want, write down the number, then go back and do the copy process. It would be good to have a button in the Add Component dialog, something like ‘Copy to New Library Element’. ---
**Author:** ![ubruhin](https://avatars.discourse-cdn.com/v4/letter/u/c89c15/32.png) [@ubruhin](https://librepcb.discourse.group/u/ubruhin)\ **Post date:** [July 17, 2023, 10:14am UTC](https://librepcb.discourse.group/t/is-this-existing-library-component-the-one-i-want/560/4 "2023-07-17T10:14:39Z")
Yes, I totally agree there’s still room for improvements 🙂 I give my best to improve the usability, but it takes time… ---
**Author:** ![4Springs](https://avatars.discourse-cdn.com/v4/letter/4/ee59a6/32.png) [@4Springs](https://librepcb.discourse.group/u/4Springs)\ **Post date:** [July 17, 2023, 10:15am UTC](https://librepcb.discourse.group/t/is-this-existing-library-component-the-one-i-want/560/5 "2023-07-17T10:15:51Z")
By the way I have figured out why I wasn’t seeing the ‘Copy from existing element’ option. I was opening Library Manager, then choosing My Library, then pressing the button Open Library Editor. From here I would right click in the Symbol, Device etc., and choose ‘New’. This way doesn’t give the option of copying. It would be nice if it did. ---
**Author:** ![ubruhin](https://avatars.discourse-cdn.com/v4/letter/u/c89c15/32.png) [@ubruhin](https://librepcb.discourse.group/u/ubruhin)\ **Post date:** [July 17, 2023, 10:23am UTC](https://librepcb.discourse.group/t/is-this-existing-library-component-the-one-i-want/560/6 "2023-07-17T10:23:19Z")
> [@4Springs](#): > > From here I would right click in the Symbol, Device etc., and choose ‘New’. Yeah actually there’s a “Duplicate” menu item which is the easiest way to duplicate a library element since you can directly select the library element to copy. But it works only if source & destination of the duplication are within the same library. Maybe it makes sense to add a “Duplicate from…” menu item, to allow selecting a source library element from a different library.