Root Weld spacing gauge:Easy operation determines rootweld spacing 1. Unlock the retaining screw and insert the gauge interior alignment stops between the two pieces of pipe to be fitted 2. Insert the leg with the longer taper into the root gap until it makes contact with both slides of the gap. 3. Re-lock the retaining screw, remove the gauge and read it 4. The scale is calibrated in fractional dimensions from 1/32 to 3/16 in 1/16 inch increments, the read-out you receive represents the amount of rootweld gap DIY Supplies:Metalworking Model Number:2924043 Internal Hi-Lo gauge: 4 quick steps check internal alignment You can check the internal alignment of you fit-up quickly with the Hi-Lo gauge 1. Unlock the retaining screw. press the gauge legs beyond the barrel 2. Insert the legs (wired) into the root gap space or the two pieces of pipe to be fitted, turn the gauge 90, being careful to apply a constant back pressure to the barrel 3. Hold the gauge as square as possible with the fitting to obtain an accurate reading. lock the retaining screw. reverse the 90 turn and remove the gauge, you're now ready to read the increment opposite the red line 4. When the red line aligns with the 1/32 increment line you have a good internal alignment and fit-up. misalignment can be determined from the zero line by increment marking of 1/16 inch Color: black, silver Material: Stainless steel Package Contents: 1 * Wedling Single Purpose Gauge 1 * Portable leather bag 1 * User manual Only the above package content, other products are not included. Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.