1.Exact replacement: 57-21-1 Carburetor Leak Detector for 705-020 2.Upgraded Vision: Carburetor Pressure Gauge is both quality and measurement are upgraded. Measurement range: 0-200kpa(0-29psi). range and more accurate measurement. 3.Excellent carburetor leak detector: Fit for 57-21 705-020, used to test whether and other 2 cycle carburetors for leaks, replaces PG-2, Tillotson 243-504. 4. Set: Comes with extra 4 sizes of fuel line hose. I.D. 1/8inch O.D. 3/16inch(3mmx5mm), I.D. 0.15inch O.D. 0.27inch (4mmx7mm), I.D. 0.23inch O.D. 0.47inch (6mmx12mm), I.D. 3/32inch O.D. 3/16inch (2.5mmx5mm), each 2 feet. Can be applied to models. Interchange Part Number:57-21 / 57-21-1 / 705-020,for Tillotson 243-504 ZPG-2 705-020 This is non-original aftermarket product. Installation instruction is not included. Note: Installation guide not included, Please check as much as possible to make sure the item is what you need. Tips: The product may be updated constantly ,Due To Different Batches, The Actual Product May Have Slight Differences Or Color Differences, Which Does Not Affect Use Color: As Shown Material: Metal Package Contents: 1 x Carburetor Leak Detector Pressure Gauge Kit Only the above package content, other products are not included. Note: Light reflection 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.