The Red Rat grip covers that we carry have really been a nice innovation for tattooing. The rubber cover really helps absorb the vibration from a coil machines and offers a better handle, that helps with hand fatigue. Getting them on can be a pain until you apply the secret that I learned from owning a BMX bike in the 80's. You've got to treat them like they were Oakley B1B grips you are trying to get onto those CW racing bars.
All you need is a cup of warm soapy water. Like a 10 parts water to 1 part dish soap works pretty well. The heat of the water helps relax the rubber and the soapy water will help it slide right over the grip. It also helps if you use our Red Rat Ready Grips, that have been designed to fit snug inside the Red Rat covers.
Then let it dry overnight and you should be good to go. If you need to remove the grip cover just reverse the process. Always keep you grip covers clean and dry, don't let them sit overnight in any liquids. This will shorten their life span for sure. I have seen people also have luck wrapping them with paper towel and tape to add more grip, especially if you have a tendency to get A&D all over the place.