spark plug information AGS22C ;-

A

 = Diameter of threaded part (A = 14mm) 

B would be 18mm

G

 = length of threaded part (G = 19mm)

E = 12.7mm / G = 19mm / - = 11.8mm

- 

 = Hex diameter 21mm

 P = 16mm / - = 16/21mm

S

S = Suppressed , R = resisted (identical , resisted are cheaper to produce so are more commonly used ) for radio interference

R = resisted   /  S= suppressed

2

2 = heat range (3 , 2 or 1 are cold)

6,5,4 = medium / 90 or 70 = very cold / 1,2,3 = cold

2

2 = power tip (1 would mean standard tip)

3 = extended spark position / -/1 = standard tip

C

C = copper (P would mean platinum)

C = copper / - = standard / P= platinum / T = triple ground electrode