Easy To Use - Press the thumb lever to open gripper and connect it to the grease nozzle. Release the thumb lever, and THINKWORK will securely lock in place! Fit All 1/8â NPT Fittings - Portable grease gun coupler are works on all DIN and SAE grease fittings and attaches to all 1/8â NPT standard grease guns, mini grease guns, pneumatic grease gun and electric grease gun.