Do a little research before you buy anything. The "jig" is only half of the equation - it's what gets you into RCM. There are about a dozen different ways of getting a Switch into RCM mode, you can use a paperclip instead but it's not recommended to use for long term because you could damage your pins. If you plan on using AutoRCM, you may not need a jig at all afterwards.
Also, double-check that your Switch isn't patched. If it is, a jig won't work for you anyway.
The other half of the equation is a "payload pusher." This can be a computer or an android phone if you have the right USB-C cable. But many people choose to purchase a "payload dongle" instead, which is basically a tiny, portable computer with the sole purpose of sending a payload to your Switch. For that you might want to look at the RCMLoader One, which comes with a jig included, or you might want to look up MatinatorX's DragonInjector, which also includes a jig and they're hoping on releasing in the next month or so (they're running a limited sale of 100 units right now). Some people decide to use a hardmod instead, where they basically solder the payload pusher in their Switch so they don't need to carry it around separately.