Northtac Ronin P-12 Micro Red Dot Sight Length-(mm)_328 Fitting may be needed as

Fitting may be needed as the condition of each airsoft gun might be different

Alternatively if you cut down the PET bottle even further

GATE Nova Trigger 2E1 for ASTER V2 (Grey)

T "Suppressed" version

Prometheus hard cylinder for Marui AEG (Type C)

Northtac Ronin P-12 Micro Red Dot Sight Length-(mm)_328 Fitting may be needed asThe Northtac Ronin P 12 Micro Red Dot Sight is a compact and versatile red dot sight designed with a removable base, allowing for customizable height mounting options such as Absolute Co witness and lower 1 3 Co witness. It features a side battery housing and low profile windage elevation adjusting turrets. With its advanced LED technology, the red dot can remain illuminated for an impressive duration of up to 50,000 hours on a single CR2032 battery.