JST XH 2.54 mm Pitch 2-Pin Electronic Computer Connector IC Male Plugs, Female Sockets Housing and T-Shaped Crimp Terminal Kit. 50 Sets/200 Pieces Wire-to-Board Adapter Cable Assembly.

These are great. I use these to chain together several custom LED setups. They seat nicely, and crimps seem to hold well even when I pull the cable pretty hard. And for 50 sets, a good price for sure. Buy a crimping tool for very small crimps, and this is the set you want. The pins fit perfectly into all my breadboards, and they’re easy to solder in placer permanently from the underside.

I used these on the hotend fans for my Ender 3. It is a little bit of a learning curve to get them on right but you can just look for a video for adding these for that. I only had trouble with them because I didn't take my Ender 3 out of the enclosure when I installed the new fans. The ends that I put on the extra new fans, I didn't have as much trouble with as I could use my lighted magnifier to see the connections so those when on easier.

I initially thought that I only had one side of the connector shells in the jar. In fact, the male and female plastic halves were already joined together - that's why I only counted 50 parts instead of 100. Check this first before you panic.

I have no fancy equipment to verify that these connector shells and contacts are within the allowed tolerances of the JST-XH specification, but what I can say is that the first 10 crimps I made - attaching female pins to 24 ga wire - went smoothly and flawlessly with an IWS-3220 crimp tool (1.6 mm slot). Insertion of the crimped contacts into this kit's 2 pin shells was easy.The goal was to shorten cables from 8" to 3.5" on five 4020 fans (2 wires each). The shortened cables all mated securely with existing circuit board JST-XH sockets, and the fans worked fine. For under $10 the cost of this approach (maximum $2 per cable, completely discounting the excess shells and pins included) was worth it to me.One caveat; if you don't already have a crimp tool you would have to include that cost along with potentially "wasted" consumables as you learn to use it. Fortunately the cost of many crimp tools has become quite reasonable, even for occasional use.Of course, with a project involving only 10 wires and contacts are cheaper solutions - such as keeping the existing cable end connectors, cutting out a section of the cables, and rejoining the wires with barrel crimps or perhaps solder with heat shrink insulation. However, with these methods the very short cables would not be very flexible, nor would they look very good, IMO.Several different crimp tools are available that accept these contacts. Fortunately the one I have (noted above) works well with the contacts in this kit.The other connectors included (i.e. the remaining 2 pin, as well as 3 and 4 pin ones) I won't use right now, but for the price it is like getting them for free, and I've no doubt that eventually I'll put them to use. They store nicely in the provided plastic box.Overall for my small job there were no problems at all, other than ensuring up front that I was ordering the right JST connector variant (-XH in this case) to match my existing components, so 5 stars.

This is the set you want. Nice easy packaging. Perfect connectors every time.

I forgot to add these to my order from my electronics supplier so I took a chance on ordering them from Amazon. These are great, and perfectly compatible with genuine JST connectors.

yep

The pins and sockets are a little hard to crimp correctly. Once the pins and sockets are crimped they fit great into the correct connector and the connectors fit great to each other.