Re-usable XT Freezing Core for use in CoolBox XT and CoolBox 2XT Systems. Provides over 8 hours of below 0℃ freezing with CoolBox XT lid on and over 5 hours with lid off. Pre-freeze in a -20℃ or -80℃ freezer until frozen, then place in CoolBox XT base when ready to work. CoolBox XT holds one XT Freezing Core. CoolBox 2XT holds two XT Freezing Cores. One Each. Made in USA. Dimensions (L x W x H): 15.2 x 10.9 x 5.8 cm / 6.0 x 4.3 x 2.3 in |