Spi 15-447-6 Telescoping Gage 3/4 to 1-1/4 in 12 in

Product Description

The SPI 15-447-6 is a telescoping gage used to measure inside diameters, bores, and slots across a range of 3/4 inch to 1-1/4 inches. The tool features a 12-inch overall length handle, giving the technician extended reach into deep bores or recessed features. Constructed from hardened tool steel with a satin chrome finish, the 15-447-6 is built for repeated use in shop and field environments. The telescoping plunger locks in place once the gage is withdrawn from the bore, allowing the measurement to be transferred to an outside micrometer for a precise reading. Weighing 1 pound, it is lightweight enough for single-hand operation.

Telescoping gages like the 15-447-6 are standard equipment for machinists, tool-and-die workers, maintenance technicians, and precision measurement professionals. This gage is suited for measuring cylinder bores, valve guides, pump housings, bushing bores, and similar round or near-round internal features in both production and maintenance settings. The 12-inch handle length makes it practical for measuring deep features where a standard-length gage would not reach.

Key Features

• Measurement range of 3/4 inch to 1-1/4 inches covers common bore sizes
• 12-inch overall handle length provides reach into deep bores
• Hardened tool steel construction for long service life under repeated use
• Satin chrome finish resists corrosion and reduces glare during use
• Spring-loaded plunger locks with a knurled locking screw for accurate transfer measurement

Compatibility

Designed as a general-purpose telescoping gage for inside diameter measurement applications requiring a 3/4 inch to 1-1/4 inch range and a 12-inch handle length.

Installation Notes

Telescoping gages are transfer-measurement tools and do not display a reading directly — always use a calibrated outside micrometer to read the transferred dimension. Compress the plunger, insert the gage into the bore at a slight angle, allow the plunger to expand against the bore walls, then lock the plunger and withdraw the gage before measuring. Keep the contact surfaces clean and free of burrs to ensure accurate transfers. Store the gage in its case when not in use to protect the hardened contact points.