I love these biners so much. Takes so much weight off your rack it's amazing.

Probably not an aid climbers choice, but for free climbing they work fine. They don't give you a lot of room to work, but they are light and have a good feel. Good biner for the price as well.

I'd disagree with the above discription. I switched my entire rack over to neutrinos and have absolutley no qualms with them. They are a little smaller than other biners, but I haven't found that to be a detriment at all. They are also within 3 grams of the "super-ultralight" offerings that have since been introduced to the market.

I'm not sure I'd pay full price for them (since there are other light biners for less $), but I didn't so I have no complaints at all.

One of the first ultralights, and now showing its age. The BD neutrino is a beutifully made high quality untralight 'biner that has been left in the dust by other ultralights. No longer near the 'lightest of the light' end of the spectrum the neutrino is also rather small, making it harder to handle, and not so useful for alpine (or any gloved endevour). Without the super-ultralight and new sex appeal the price of the neutrino is the final downfall. the neutrino does have a partially hooded gate to prevent sliding over rock to open the gate which the Trango Superfly and other ultralights do not have. Cheaper, lighter, bigger biners can be had. the new WC helium (if it can ever be obtained) promises to be lighter, keylock, bigger and generally superior for more $, but reputably worth it.
Pros: well made solid ultralight, partially hooded gate.
Cons: not-so-light-anymore, very small, expensive.