

The GBRS Group LERNA is a high-rise mount designed for EOTech XPS holographic sights. It positions the sight's optical axis 2.91" / approximately 73.9 mm above the mounting rail. The elevated position supports a more upright head posture and can make the optic easier to use with a helmet, communications headset, protective mask, or night vision device. The design follows the same elevated-optic concept as the GBRS HYDRA but omits the front accessory platform.
The EOTech XPS version of the LERNA positions the sight's optical axis 2.91" / approximately 73.9 mm above the top surface of the mounting rail. This reduces the need to lower the head toward the stock and supports a more natural heads-up aiming position.
This LERNA version is specifically designed for EOTech XPS holographic sights. GBRS also offers a separate version for EOTech EXPS sights, with both configurations providing the same 2.91" optical axis height.
The LERNA uses the same basic high-rise optic concept as the GBRS HYDRA system but omits the front platform for additional accessories. Its streamlined construction is intended for users who require an elevated primary optic without an integrated accessory mount.
The elevated optic position is particularly useful when wearing equipment around the head and face. It can make aiming easier when using a ballistic helmet, communications headset, protective mask, or night vision device.
The mount body is machined from 6061-T6 aluminum and protected by a Type III Class 2 hard-anodized finish compliant with MIL-A-8625. The clamping bar and screws are made from 17-4 PH stainless steel in H900 condition and feature a Melonite QPQ finish. The washers are made from 18-8 stainless steel.
The EOTech XPS version weighs approximately 4.2 oz / 119 g. The package includes the LERNA mount and a 1/4" T25 bit for installation.
GBRS offers a separate 2.91 FTC mount for compatible magnifiers. It positions the magnifier at the same 2.91" optical height, keeping the primary optic and magnifier aligned on a common axis.
| Weight | 119 g |
| Material | Aluminium 6061 Stainless steel Steinless steel 17-4PH |
| Type of rail attachment | 1913 Picatinny rail |
