The Cryo Grid boxes are used for storing and transferring vitrified cryo-EM specimens prepared with cryo-devices like the FEI Vitrobot, Gatan CP3, Leica EM 6P, as well as other cryo vitrification systems. There are two versions of these boxes, each with 4 storage positions. The round one is the most widely used and is available in two colors and three versions: with clear lid, pin type lid, and without lid. The round boxes can be used on the Gatan 626 and CT3500 cryo transfer systems and on the FEI Vitrobot and Gatan CP3. The square Cryo TEM grid box includes a non-static rotatable lid and fits the Gatan CT3500 Cryo-Transfer Holder and Gatan CP3. All boxes have a UNC 5/40 thread in the center. On versions with clear lids, the lid is held in place with a stainless steel screw.