This is the HPI R4 Medium Cold Glow Plug for .25 size engines.
FEATURES
Cold Plug for cooler temperatures
Copper sealing ring
INCLUDES
One HPI R4 cold plug for .25 size engines
SPECIFICATIONS
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COMMENTS
Although this plug is intended for use on the .25 engines itcan also be used most nitro engines .12 to .25.
For 0.18 To 0.28ci (3 To 4.7cc) Engines 16% to 25% Nitro
Power Plugs for Nitro car and truck engines! HPI Power Plugs use a unique blend of platinum and iridium metals to produce a range of quality glow plugs that is suitable for hobbyists and racers.
Recommended Power Plugs for HPI engines:
#1502 Glow Plug Medium R3
#1503 Glow Plug Medium/Cold R4
#1504 Glow Plug Cold R5