Definitely go with the screw gate, it's safer, less expensive, easier to use, and the red band makes it hard not to screw tight.

I decided to pick a couple up to replace my BD Rocklocks in my anchor set up and I am loving them so far. I prefer the D 'biner for the rope side of the anchor and then I will use some pear shaped 'biners for the rock side of my anchor system and it works great for me. These are extremely strong, you can't go wrong. Also on the screw lock the "red you're dead" marking is very nice for a visual check to make sure it is locked down.

I have got to say, out of all the biners I've own or used over the years, this is the quickest and easiest one I've seen. The Ball-Lock is great! Only having to twist about 25 degrees, rather then the 45 on any other twist lock, means I can get it open even at odd angle where I don't have an ideal grip. Something that can be more then a little annoying when you finally topped that 70 foot lead. Plus the simplicity of just having to visually check for a green dot to know that the gate is locked is a real turn on for me.

I prefer these for belaying because they are nearly symmetrical. That means I can let it wear on each end, doubling the life of the belay biner. And the key lock makes things easy as well.

I used to use the ball locks, now I use the triact lock. I used to use manual screw locks, but prefer auto lockers for belay biners because one less thing I need to keep track of.

I went with the screw locking version. They are cheaper and simpler, which usually means they will last longer. At my local gym all top ropes are set up with the orange self locking biners and some of them are sticking and can be a pain to get on and off. Maybe some lube would fix that. But since I'm not using mine in the gym where I am bouncing between top rope lines every 2 minutes I went with the screw locking. LOVE THEM.

I have a couple of these with the Tri-act gate, and find them very useful for certain things. I wouldn't use mine with a tube device or for rigging anchors (though I'm sure they would work fine), but they work great for a GriGri and are nice because they always stay locked and are easy to visually confirm. Also, I use one on a Mini-Traxion for solo top rope, which works well because (again) it stays locked when moving around with it, and the pulley has no trouble swinging around on the biner to load it in the proper orientation in case I fall on it.

This biner is great for building anchors because it is symmetrical and the keylock nose never snags on anything. The only downside is that it is heavy and kinda expensive

I´m a Rescue Firefighter and this carabiner is excellent for many applications: Anchoring, Pulleys, Descender, Ascender... I also do a little rock climbing and I find it quite light for a piece of equipment that safe. So gear up and take it to the top.

This is great cuz you never have to worry about your belayer not locking the gate. I find it a little annoying - you have to pull the screw up, twist it, then you can open the gate. But it is safe! And quite large and durable.

If there is one locking biner to end all, this is it! My go to for anything that needs to be bomber without giving it a second thought. This or the William are always on my harness for anchoring. The gate action, after years of use are still like new. I would buy these over any other large locking 'biners anyday.

this is a fantastic biner. it allows room for error, especially when building anchors. one hand operation makes setup super quick, so you get the maximum number of climbs in on that well-earned saturday. just be sure your climbing buddy understands the whole ball-lock concept before he goes up to clean the anchor :).

It is really tough and larger than my other carabiners... It has a good lock w/ a red warning strip shown if its unlocked.. a good warning strip for safety purposes...Its just heavier than my other carabiners.. an additional weight load to my stuff if you carry to many of them but in terms of safety it worth it.

Excellent biner. I also like the red safety stripe. The Am'D fits tight into my Petzl Pirana Descender making it feel like one unit. Great price for a quality carabiner.

Petzl Am'D Locking Carabiner is a must for any climber

Ok I'll add to the love :-) Biener of choice when I start to build up an anchor. love the safty red paint on the screw lock! Why is this not the standard?? I plan to mod my others this same way! Buy two or more :-)

Favorite locking beaner. Easy to use and never have to worry about remembering to screw the gate shut

The Ball Lock is a nice little invention. The pic here on the site makes the lock barrel look plastic but it is aluminum. A quick glance and as long as you see green you know it's locked. Nice smooth one handed operation too. I used a piece of rope and tangled it around the gate every which way I could but I could not get the rope to move the lock. Time will tell but I don't see any way this could come open accidentally.

First Ball Locker biner I have, and it rocks. Like previous reviews, the throw with the ball is shorter and easy to open than other lockers with one hand once you do it a few times. Less wrist twisting and contorting just to put on you belay device. Great addition to the rack.

Smooooth screw-gate, big enough to get a lot of rope/sling in there. Has a more "solid" feel than my Black Diamond Rocklock. They're both safe, of course.

I also like the added touch of the red paint that *only* shows when this biner is not locked. I don't need a feature like that to keep me alive, of course, but it's an extra safety measure that has no real downside.

I have a couple of these carabiners in a Triact-lock. The lock is secure, yet quick and easy to open one-handed. They are a little more money than some other carabiners, but still pretty good for the price.

i love the am'd carabiners. i recently bought this auto locking am'd for my reverso 3 and found that it is a not worth the extra five dollars. it get locked up about halfway open on me very often, making the ease of the one hand operation not so easy. otherwise i love that it locks automatically, makes it easy to perform the once over before climbing.

As the title says it, this biner's locking action is way smooth, easy to lock and un-lock while wearing gloves or mittens, and is great for attaching an ATC. For the price and quality, you cant really go wrong here.

I dig it, just ordered some more. It's quicker than the screw and safer than most biners.

I find this biner a bit awkward. After using it several times, it's still taking me two hands to get it to open, but I feel confident that I'll get used to it and I consider it safer than the screw versions which I can be prone to forget about closing. So, works for me.

Can't stop playing with the gate! It's so much fun to try to open it with one hand because you need to lift and turn it. Also looks very cool... Oh and it works fine :P

This is a very reliable piece of equipment. The triact lock is positive and easy to operate with full finger gloves. Ball lock is a little more difficult and not as "robust" in my opinion. Twist lock is cool with marking to identify if locked or not. Great LOCKING Carabiner.

For the price the best beanier I have used on the climbing wall at my waterpark climbing wall. Doesn't corroide under the chlorine in the water.

Works well and priced right no matter what you using it for they are always nice to have handy in a pinch... pick one up

works well, fast and easy to use. Good price also.

These are pretty burly.  I am a much bigger fan of the screw lock.  I have the triact lock attached to my Metolius PAS - but they are too tough to open/attach with one hand - so I often just use the screw lock. Which are really easy to open/spin closed with one hand. 

I'm just getting into climbing & the Petzl Am'D Locking Carabiner is great for me: I never have to worry that my carabiner is not locked! I bought the Triact-Lock Auto Lock version. Ya know, better safe than sorry, as Mom used to say...

It took me a bit to get used to this carabiner (Triact_Lock), but I like it. I have my 4 year old daughter use this with her setup and it gives me peace of mind. It is good for what I use it for, but I probably won't buy any more just because it has been difficult for me to get used to it. I would take a regular screw-lock over this for most locking carabiner needs.