We offer 12" riser plates for the GT-10 and GT-15 models. The machines original table is 24" so if you want to use tool holders on the entire travel of the models you would purchase two 12" riser that would cover the original t-slot of the machine. This flexibility allows us to install much larger live tool spindles and grinders on the machines and allows us to offer much stronger tool holders and tooling to compliment the larger motors and ball screws of the machines. Optional center height riser tool plate tables available on request.