What are the purpose of a crank or flash noseband?

Please forgive the stupidity of this question, but inquiring minds (okay... just me) want to know. Throughout my short-lived riding career, I rode in primarily western tack. A few months before I quit riding, I found myself on a horse that wore English tack and fell in love with the style. This horse wore a plain raised snaffle bridle and I didn't have much of an opportunity to learn more because I quit riding shortly thereafter.

Now, I'm researching English tack for my new horse and I've come across these curious bridles advertised as 'flash' and 'crank'. What are their purposes? How are they supposed to be used? On what type of horse would you use something like this? I've tried Google and there are a lot of pictures of each bridle, but nothing that really answers my questions. So far, I've found that these bridles are used to keep a horse's mouth shut - is that the only reason?

For the record, I plan to start my mare in a simple snaffle bridle with some sort of mild bit - I'm thinking a French link d-ring to prevent any pinching. She's a retired harness racer, but has been off long enough (11 years) for me to hope that her mouth has softened up considerably and she won't require a harsher bit.

Flash nosebands are a regular cavesson noseband with another strap of leather which fastens underneath the bit and keeps the horse form crossing his jaw or gaping his mouth to avoid contact. It is slightly more "severe" (I say this loosely..) than a regular cavesson. A crank nose band is like a cavesson only it goes through 2 metal rings which pinch the back of the nose band around the horse's nose.. so it's a more snug fit. Some people use it like a regular cavesson, allowing a finger's space between it.. others make it very tight so the horse can't cross its jaw or gape it's mouth..

Personally, I wouldn't use them on my horse but I know a lot of respected and knowledgeable riders do.
I did, however, just buy a bridle in XL (his was horse and he is an XL sized head) for my horse and it came with a crank nose band and I'm planning to use it more like a regular nose band in regards to spacing.


Sorry no one answered till now!

Thanks! As I was shopping around for bridles to fit my mare's giant head (she's somewhere between a horse and warmblood sized bridle), I discovered that it's next to impossible to find JUST a snaffle bridle. Most have a flash on them. So, I had to buy a bridle with a flash noseband. Not exactly pleased, but I was able to remove the extra strap. Good enough.

Here's hoping this bridle fits, because I think it's really pretty and will complement her dark coloring. Heh.

Flash nosebands are used only to stabilize the loose ring snaffle in the horses mouth to keep the connection quiet and the horse sensitive to small aids.
A flash or crank or both will have relatively little affect on a horse crossing his jaw - this is what figure 8s, grackles and crescent nosebands are for.
Crank nosebands are able to go tighter than normal nosebands - but should really only be adjusted "normally". They are a good thing to try - and tightened - if the horse is prone to putting his tongue over the bit. They also tend to lay nicer on the horse.
Posted via Mobile Device

I removed the flash on mine as well, I just don't feel its necessary and its still a beautiful bridle without it.
ETA: I use a Kimberwick bit (has a curb chain) which is another reason I don't use the flash.