Widely used for Handgun Airgun Shotgun cleaning tools. Designed for Calibers including. 177caliber. / 4.5mm.204caliber / 5mm. 22 caliber 5.56mm.243 /. 25caliber /6.3mm.270caliber 7mm. 30 caliber 7.62mm.33 caliber 8.5mm. 357 caliber 9mm. 375 /. 38caliber 9.3mm. 40 /.410 caliber 10mm. 44caliber. 45 caliber.5 caliber,12 Ga. 20 /16Ga.