How to measure T-slots on a Drill press table?

T10440 - Precision 3-Way Drill Press Vise drill press clamp tslot Use drill press or milling machine hold down kits to keep your quality work piece in place Choose a sturdy T slot clamping kit from Busy Bee Tools drill press clamp tslot Quick Acting T-Track Hold Down Clamp with T Bolts Silder Aluminum Alloy Woodworking Clamps for Routers Drill Presses Table Saw Clamp for T-Slot T-Track

t slot clamps I built a special base and anti rotation arm to make quick work out of clamping the vise to the drill press table tee slots which don't match