The 1" cross hole and the two vertical holes accept boring tools or bars with a 1" shank diameter. A 1-1/2 - 18 threaded back permits the use of a variety of shanks.
Distance Between Hole Centers: 1-1/4. Outboard Hole Boring Range: 3" to 7". Cross Hole Boring Range: 5.625" to 13.437". Overall Length (w/ shank): 8-1/2.
Comes as shown in pictures.