I just installed a new vanity in our cabin. The supply lines that come up are Pex. Is there an adapter from these to the faucet lines or is there a better way to make these connections? Thanks in advance for any help!
I would suggest Sharkbite straight stops. Slice the PEX nuts off and discard.
I recommend a PVC/PEX plastic cutter for safety and relatively clean cuts.
Like @breplum indicated but more detail: it looks like from the photo that you don't have stop valves on those ½" PEX supply lines; if you don't, you definitely need them. The SharkBite (other brands too, such as Watts or BlueHawk along with some compression fittings) comes in a ⅜" compression (what you need to connect your faucet lines to) with a ½" Sharkbite on the other end (to connect to your PEX) and the shutoff between them. Any home center should have these. Note that despite the fact that these are ⅜" compression on one end you are not using compression fittings; the ends of your faucet lines are ⅜" thread with an o-ring.