O.S. Engine - Glow Plug #R5 Cold  [OSMG2694]

QUALITIES:

Made for high nitro fuels. (25% +)
Increased durability at high RPM.
Durability under extreme temperatures.
Allows for "leaner" needle settings for greater power
and faster throttle response.
This plug is best suited for 1/8 scale, .21 gas driven on-road
racing.

Choosing the Right Glow Plug? Please make reference to these link.
http://www.osengines.com/accys/choosing-glowplugs.html