Designed using real-world dimensions, the lenses replicate the exact size of the genuine 737 Boeing Korry units, ensuring an unmatched level of authenticity. The outer case, rendered in high-quality resin, is deliberately dimensionally larger than its metal counterparts, due to the use of resin over metal construction. 
 
Engineered for Exceptional Performance
The V2 Annunciators are the pinnacle of Karl's Engineering—fully pre-built and crafted with the finest components available in limited space. Upgraded from the previous generation, these units now feature the advanced soft-press ALPS buttons with an enhanced push force and longer travel distance, outclassing the 6x6 mm LED tactile switches used in V1. All SMD components, including two ultra-bright SMD LEDS, are seamlessly integrated into each unit. Built with the correct 5v resistors, these annunciators offer a plug-and-play experience with Arduino—no extra resistors required.
 
Innovative Connectivity & Versatile Integration
Designed as a common Ground/Cathode unit, each annunciator comes equipped with three dedicated pins:
GND
LED
BUT (button/switch, configurable for acknowledgement or cancel via Mobiflight)
 
This simplicity in design ensures straightforward installation while maintaining flexibility for various integration setups.
 
Enhanced Visual Impact
Every annunciator is outfitted with white LEDS paired with colored acrylic lenses and a diffuser lens. This deliberate choice of components guarantees that the unit “pops” when illuminated, delivering a striking, even glow that elevates the cockpit’s visual appeal—even when mixing lens colors.
 
Custom Installation Options
For those looking to secure their setup further, each unit offers the option to add a resin-printed backcage and mounting hardware. (Note that users of the 737SS build do not require the backcage.) 
 
A Dimension info PDF can be found here.