Features: The cable railing kits is selected from aluminum. The drill guide have hardened plate steel sleeves to prevent wear and misalignment during drilling. The drill guide jig have a large clamping area for easy use without covering holes. Clear mark on four side of the drill block show the hole centers for precise use. There are 3 angles (30°, 45°, 90°) and 4 hole size (3/16" (4.76mm), 1/4" (6.35mm), 5/16" (7.93mm), 3/8" (9.52mm)). You can freely choose for cable railing systems. The 1/4” hole fit 1/8" cable railing lag screws and protectors sleeves (see fifth images for details). The drilling hole guide jig is portable and pocket - sized. Suitable for cable railing installation and woodworking. The side hole guide lines can clearly and accurately position your drilling fixture, making it easy and more convenient for you to use. Specifications: Component:Aluminum Type:1/2 Size:Approx.105x70mm/4.13x2.76inch Package Includes: 1Pc Drill Guide note: 1.Please allow 1-2cm errors due to manual measurement, making sure that you not mind before order. 2.Due to the differences between different monitors, the picture may not reflect the actual of the item.