Aim-O Advanced 551 Open Red Dot — Black

The Aim-O Advanced 551 is an open-tube red dot with a dual red/green reticle, designed for use on carbines, semi-automatic rifles and airsoft replicas fitted with a standard Picatinny or Weaver rail. The construction combines a metal chassis with rigid polymer panels, keeping weight down without sacrificing the structural integrity needed to handle recoil.

The reticle can be switched between red and green, with brightness adjusted via the rear keypad — the same panel that handles power on and off. This puts all controls in one place, accessible without moving the hand from the grip. Power comes from four AG13/LR44 batteries housed in a lever-release compartment that can be replaced quickly in the field without tools.

Windage and elevation are mechanically adjustable, so the point of impact can be corrected after zeroing without relying solely on mount adjustment. Attachment uses a single-screw system compatible with Picatinny and Weaver rails: quick to install and remove, but worth checking for tightness after heavy shooting sessions with hard-recoiling calibres, as the single screw offers less contact surface than lever-lock systems with dual anchor points.

Key features

• Selectable red or green reticle with adjustable brightness: adaptable to ambient light conditions without tools.
• Unified rear keypad for power, colour and brightness: full control without changing your grip.
• Lever-release battery compartment for four AG13/LR44 cells: fast replacement, no tools needed.
• Compatible with standard Picatinny and Weaver rails: fits the vast majority of platforms in common use.
• Metal body with rigid polymer panels: structural strength at reduced weight.

In the box

• Aim-O Advanced 551 red dot