This is a set of genuine BMW exhaust tips that should fit E84 X1 model 20i, 20iX, 28i, 28iX. From what I understand they come standard on all Sport Line models – see discussion here:
http://e84.xbimmers.com/forums/showthread.php?t=781313
Both tips are in great cosmetic shape. I purchased them in September from BMW Seattle for my X5. To fit on slightly larger X5 tailpipes I had to remove some of the metal strips/hold clips from the inside (see pictures). You should still be able to secure them tightly on X1 tailpipes with either piece of metal strip in between the pipe and tip or by further bending the metal ring that is on the edge of the inner side of the tip. Please note these are slip-on so no cutting/welding is required.
External diameter is 70mm. Inside diameter with metal clips attached (original tailpipe size) is 67mm. Angle cut end: short bottom side is 55mm in length, long top side is 85mm.
Realoem.com parts list:
http://www.realoem.com/bmw/showparts...18&fg=20&hl=12
For vehicles with Sport Line (P7ACA=Yes)
Tailpipe end piece, alu-look - 18307635633
Paid over $120 at the dealership, selling for $60 for both + shipping (paypal)