The Tube Support is designed for holding 2" to 4" diameter processing tube in MTI GSL 1600 - GSL1900 tube furnace. One pair of tube support can be fixed to the top and bottom of the steel protection ring and keep the processing tube from bending under high temperature (>1600oC ) due to the weight of the flange. •You need enlarge hole on the protection ring to put tube support in. •One furnace will need two pairs of support to keep the tube straight. •See picture below to learn how to install.