Genuine ngk bkr6es spark plugsuitable for the following modelsmountfield castel stiga rs100 rsc100 engines 5750 series engine 5750 series now renamed as st250ngk equivalent to 118550658 0 k7rtcfits the following models with rsc 100 enginesmountfield s421rhps421rpds421hp295431043 m12s421pd295432043 m12s461rhphp46r 299484043 bqfits the following models with rs 100 enginesmountfield hp164 297411048 sfsp164 297412048 sfhp180r 299484043 m16hp41 297411048 m17hp42r 299434143 bqhp45 299014643 bq299174648 m17molemaster 46hp 299174648 m16hp414 rs100 297411043 bqsp414 rs100 297412043 bqsp180r 299489143 m16sp41 297412048 m17sp42r 299439143 bqsp46 299274643 m13s421hp rs100 295431043 m12 s421pd rs100 295432043 m12s421rhp rs100 299434043 m14s421rpd rs100 299439043 m14s461hp 295485043 m12stiga47 blue rs100 298471048 s15multiclip 47s blue rs100 298472048 s15collector 43 rs100 295431048 s14collector 48 295481048 stxfits the following models with 5750 series st250 engines827h series 5750 ohv 224cc 2t0070483 m16 2016827m series 5750 ohv 224cc 2t0050483 m16 2016r27m series 5750 ohv 224cc 2t0070486 sf 2016stiga 1066h2t0070481 16series 5750 tre224 224cc 118551159 0