Grippers: James
I use the grippers from Ironmind. They are very high quality and will prove a challenge to anyone that picks one up. The grippers I use vary from:
#1 140lbs to close This is the one in the video below for more than 100 clicks
#2 195lbs to close This is the one I do a lot of work with
#3 280lbs to close I still can't close this one yet, a few mm left
#4 365lbs to close I can barely budge this one.
From the left: older #1, older filed #2, newer #2, older # 3, newer #3, older #4.
I have more than one of some because they each have slight differences in hardness to close.
I filed the edges of one of the number 2's to make it more difficult to close.
Ironmind #1 Gripper
Number 1 Gripper over 100 clicks
Ironmind #2 Gripper
Disclaimer: These activities involve manipulating items in ways that they were not designed. These activities could result in serious injury or death. Do not attempt without understanding the risks associated.