spiral glow plugs with heating coils for diesel engines
Coil from resistive material. For older design of diesel engines. Glow plugs without regulation. Used in a series connection circuit, mostly with heating indicator light from the same resistive wire as the heating coil
| type | M | L | B | S | U [V] |
| 33.50 | M18x1,5 | 91 | 21,5 | 21 | 0,9 |
| Z25 | 125 | 30 | 1,7 |