I've had this in my 335i for a little over a year, replaced at 107k miles preventitavly. When taking the stock plastic flange out, it immediately crumbled into three pieces. This is a necessary and inexpensive piece of maintenance that should be done preventatively no matter the mileage of your car. I generally avoid Rein parts as their quality has gone down since Covid however I have had no issue with the part nor the o-ring that comes with it. Be careful to avoid overtightening the two bolts, highly recommend this part!

It was recommended that I replaced this part in their youtube video. I wish I would have replaced the expansion tank as well as it cracked ~1 month after and appears to be made of a similar plastic of the OEM flange.

As others have stated, this part is good but the o-ring failed in about 1-year/12,000 miles. The o-ring was hard and fell apart when I removed it. I was able to find a viton replacement at my local hardware store but I would recommend ordering a BMW o-ring to go along with this part. Part number 11537545278 is available from FCP Euro

I was worried about the plastic flange breaking, leaving me stranded. The old flange was difficult to come off, as it was not completely worn out yet. I had to cut the metal clamp off with a dremel. I feel much better now that I have a metal flange

Got the part when the original plastic one crumbled when replacing the oil cooler gaskets. Aluminum item works great. Fit first time, no problem. But, since then, the fitting is leaking from around the o-ring. The provided o-ring was completely flat and brittle on inspection. Need the o-ring size to replace it with something more robust and less likely to leak after only a very short time.

Don't get stranded. great part! beats the old plastic ones.change your now

Part fits great and sealed when installed. O-ring failed in 12 months. Upon removal, o-ring was flat and brittle.

This mickey mouse piece is great, easy replacement for that weak plastic piece, highly recommend to replace radiator into an aluminum with new hose so you wont have any cooling problem or hosing problem for a while.

Flange part fitment was perfect! Recomend buying new mounting hardware for this as the stock bolts can snap easily.

I replaced this as a preventative maintenance item when doing my oil filter housing gasket. Make sure to order the bolts too since the heads are usually rusted. Also, make sure to lube up the o-ring with a decent amount of coolant so it slides on easily, you'll have to push it on. Initially, mine didn't want to sit flush on the bottom but after using more coolant it slid in easily.