If you need to feed an orphaned lamb or kid, you want a soft teat particularly at the beginning to get them used to drinking from a bottle.
These latex teats are 'baby' quality. The natural teat is very soft, ideal as a starter teat for lambs or kids.
The hollow-cone tip can be cut off at the desired milk flow rate: the closer to the teat, the faster the flow. Err on the side of caution and cut it smaller first particularly for small or weak animals. This will also help avoid the chance of milk aspiration which can cause pneumonia and death in extreme cases.
Teats pull easily over normal 28mm neck soft drink bottles.
There is no air inlet on the teat. If you have a very vigourous drinker, this will cause the bottle to collapse during feeding: you can avoid this by periodically moving the bottle or by slipping a finger under the rim of the teat and allowing some air to come in.