I have these and love them. DIMRS DIMRS Self Adhesive Nipple Covers - Nude-1 pair https://www.amazon.com/dp/B002P98WMM/ref=cm_sw_r_cp_api_glt_fabc_T8HMW713SBCHTJNRBZKG
Different fabrics react differently with bras I recommend these dimrs. I found them at a local bra shop and it doesn’t matter what bra/fabric combo you wear
https://www.amazon.com/DIMRS-Self-Adhesive-Nipple-Covers/dp/B002P98WMM
I use these in unlined bras and have been very happy with them.
I use these regularly.
I'm going to be the devil's advocate and *not* recommend spacer foam as the #1 for nipple concealment, because it's my understanding that spacer foam bras are more about comfort; and this is achieved b/c there are no seams to "direct" breast tissue to go a certain directions (a.ka. vertical seams direct breast tissue up, horizontal seams create a more rounded look across the cup instead of pointy), instead the spacer foam conforms to one's own breast shape.
It might be helpful to read some of these reviews https://www.bratabase.com/browse/fantasie/rebecca-2024/ two of the first four reviews say, "not great for nipple concealment" or not great for prominent nipples. Some of the reviews also say that they sweat more in their spacer foam bra than they do in their cut & sew bras (seamed bras) in the summertime.
It could still be worth a try-on if you're looking for a comfortable bra, not nec for shaping though, because it will just conform to one's natural breast shape.
I would order from a place with easy returns, and keep the tags on when you check it out! One alternative could be using something like what u/BVO120 suggest, nippies, I know there's also something called DMRS nipple covers, but I didn't realize they were so expensive.
I sort of found the right bra. I got the Calvin Klein Lightly Lined Demi. It's not quite a pushup, and the padding is fairly thin. You can see it's a foamy translucent material. You can certainly tell if I'm cold while I'm wearing it if I don't wear a thicker top. I first tried wearing it with Dimrs underneath, but found that to be very uncomfortable. The bra by itself was very comfortable, and the underwire definitely gave me the support and definition I wanted. It's almost perfect. I wish it had push-up padding, but for a travel bra it is great. I even bought it in black for significantly cheaper at Century21 in NYC during a short trip. It dries in about 2-3 hours after washing too, which is great.
The Ibex Balance Brief is great! I took two on a two week trip, and didn't have any problems. I'll get a third for next trip so I don't feel as pressured to get home and wash at the end of the night if I have a lot going on any specific day.
I just tested out the Ibex Balance Brief a couple of days and loved it. I had no idea wool underwear would feel so comfortable. I hope they last a while because they were a bit pricey.
I also like wearing an underwire although I'm only a 34B. I realized that without one, I feel like the bra is very flattening. I haven't seen a wool bra, but I'm testing out two new bras I picked up at L&T.
Both fit nicely and don't flatten me out. I wish I could add a little bit of padding, but the silicon cutlets (opt. 1 and opt. 2) I got on Amazon look lumpy under these.