The Whispah linear slide is a low-cost component providing very smooth and quiet motion. The stable, two-rail slide is available in two sizes. The WSP 1 twin-rail system features a 4 x 5.50 in. table with a bearing centerline to centerline measurement of 2.125 in. For greater load and higher stability, the WSP 2 twin-rail system features a 6 x 7 in. table and a bearing centerline to centerline of 2.906 in. Either slide can handle vertical loads up to 150 lbs. and side loads to 75 lbs. LM76 LINEAR MOTION BEARINGS, East Longmeadow, MA. (800) 513-3163.