A used one, with o-rings, filter installation instructions, and an OEM part box. No filter.

This is the original that was on my XF, but the prior service person put it on so tight that I had to use a metal pipe wrench to loosen it. The result is some teeth marks on the cap. So still serviceable, but cosmetic flaws.

US$15 plus USPS First Class Package (w/ Delivery Confirmation) S&H, plus optional USPS insurance (otherwise shipping is at your risk). PM me with your zip code when interested. Paypal (no eChecks) or USPS (Post Office) money order.