No one has ever closed the 500. You are gonna have a very tough time finding the 400 and 500 because they were limited edition and are sold out now. I know they made a 350 but I don't know where to get it...
NO one has ever closed the 500?? then how come they produced it??
actually i know where to find the 350, 400 and 500...not that difficult to find...but because i may need to buy 350 in the future...i'm not telling anyone where i can buy, sorry about that...i don't want it to sold out...
I'd say most people CAN'T close the 350 in their lifetime. Look at the people caertified for closing a CoC #4 which is 365 lbs. There are only FIVE CERTIFIED! Sorry to burst your bubble. Even if you have great genetics, it will probably still take several years of constant grip work at least.
If a person can barely close the 150 than it's probably going to take 5 or more years of steady grip training to close the 350 (if ever). I started with the Heavy Gripper 150 and 200 and grew out of them quickly. I decided to go up in resistance but accidentally ordered the #3 Captains of Crush (different brand 285lbs.)which are just a little bit much for me. My point is that I have a pretty strong grip and the 285lbs. Captains of Crush feel damn near impossible to close completely. I can't imagine being able to close 350lb heavy grippers anytime soon. I would suggest waiting to buy more heavy grippers until you can successfully close the 200 3-4 times. After that you could go to the 250 and work on it until you can close it once, and then close it 3-4 times, and then go up in resistance again and so on until you are happy with your grip strength. Good luck!
Grippers train crushing grip and they can also be used to train supporting grip. Crushing grip is the ability to close your hand and supporting grip is the ability to keep your hand closed, so CG is analagous to hand strength when SG is analagous to hand endurance. Powerlifters obviously develop both types of grip, but supporting grip to a much greater extent.
I don't think that being able to DL 700 lbs strapless is equivalent to closing a 350lb gripper, especially since poundage ratings on grippers are more of an estimate than anything.
The high level grippers that nobody can close exist so that people with high level grip strength can use them to do negatives or static holds (ie: starting them off with two hands and finishing with one) to train supporting grip.
I purchased the 5 piece set of HG. 100,150,200,250 & 300. I started able to close the 150 and close to 200. I have been using my grippers for 4 months and I am really close to closing the 250 now. Also as far as your deadlift analogy I have only deadlifted 455 yet I can just about close the 250. Keep at it it just takes time.
the thing with your grip in weight lifting is its not crush grip its just you holding onto something, not trying to crush it with your hand, theres many many different types of hand grip, the dead lifting and farmers walks and all that work crush strength to an extent but mostly grip endurence like someone said earlier.
if you want a total grip your going to need to work all areas of your grip including the opening of your hand motions, as you body naturally will not let you grow too strong in one muscle so you do not injure yourself