A vertically adjustable scope base designed to mitigate parallax induced aiming errors. The apparatus comprises a rail assembly, a front base, a rear base, a pivot fastener, an incline mechanism, and an incline adjuster. The rail assembly comprises an optics mount, a pivot mount, an inline mechanism mount. The front base comprises a pivot mechanism. The rear base comprises a threaded sleeve. The front base and the rear base each comprise an attachment mechanism to mount the apparatus to a weapon system. The Incline mechanism comprises a housing, a first and second bevel gear, and a threaded extension rod. The incline adjuster comprises an axle assembly, a dial, and a base. The configuration of these components and sub-components allow a user to quickly and precisely adjust an optical sight's angle of incline instead of repositioning the reticle to align the crosshairs with an intended point of impact.