The Exposure Diablo MK12 is twice the price of some lights but it has the best head mount, it’s super powerful and has a usefully tight, focused beam.

Product Overview

Overall rating:

Score 10

Exposure Diablo MK12


Exposure Diablo MK12 light review


Price as reviewed:


Every year Exposure updates its lights, and having tested the MK11 twelve months ago we’re now on the Exposure Diablo MK12, which is a similar price and weight but gets an extra 100 lumens.

Read more: Best mountain bike lights – find your flow in the darkness

All Exposure lights are programmable and all the settings are handily etched on the back of every light. To access these OMS (Optimised Mode Selector) modes on the Diablo Mk12 is not as easy as the Exposure Maxx-D because there’s no read-out, but you simply press and hold the on/off button and count the flashes. The modes allow you to vary the power/burn time or reduce the settings from three to two, but the one we’re most interested in is the ninth setting, which is the Tap Technology. Once activated you can just tap the side of the light to change from high to low beam; no need to fumble around for the on/off switch on the back of the light.

Exposure’s long standing helmet mount is one of the best out there. It fits easily through a helmet vent and has a tilt adjustment built in. It even comes with a security leash, so if the light gets knocked out of the mount it won’t disappear into the undergrowth.

The Exposure Diablo MK12 is twice the price of the other lights here, but it’s the most powerful and has the best light quality and beam pattern. The only slight chink in its armour is run time, especially as you can’t actually see the battery life indicator when it’s on your head, although your mate can.

Exposure’s all-in-one, cable-free design does add weight to a bar light, but as a helmet light it makes total sense. The Diablo MK12 is convenient, powerful and totally user friendly, it’s also excellent quality and easily the best lid light on test.


Lumens:1850, 1000, 500
Run time:1, 1.5, 3hrs