le ▁of ▁a ▁be er ▁engine . ▁Design ed ▁rather ▁like ▁a ▁show er - head , ▁be er ▁disp ensed ▁through ▁a ▁spark ler ▁becomes ▁aer ated ▁and ▁fro thy ▁which ▁results ▁in ▁a ▁notice able ▁head . ▁More ▁CO 2 ▁is ▁carried ▁into ▁the ▁head , ▁resulting ▁in ▁a ▁so fter , ▁swe eter ▁flav our ▁to ▁the ▁body ▁due ▁to ▁the ▁loss ▁of ▁normal ▁CO 2 ▁acid ity . ▁ ▁There ▁is ▁some ▁dispute ▁about ▁the ▁benefits ▁of ▁a ▁spark ler . ▁There ▁is ▁an ▁argument ▁that ▁the ▁spark ler ▁can ▁reduce ▁the ▁flav our ▁and ▁a rom a , ▁especially ▁of ▁the ▁h ops , ▁in ▁some ▁be ers . ▁The ▁counter ▁argument ▁is ▁that ▁the ▁spark ler ▁takes ▁away ▁har sh ness . ▁▁ ▁Bre wer ies ▁may ▁state ▁whether ▁or ▁not ▁a ▁spark ler ▁is ▁preferred ▁when ▁serving ▁their ▁be ers . ▁Gener ally , ▁bre wer ies ▁in ▁northern ▁England ▁serve ▁their ▁be ers ▁with ▁a ▁spark ler ▁attached ▁and ▁bre wer ies ▁in ▁the ▁south ▁without , ▁but ▁this ▁is ▁by ▁no ▁means ▁definit ive . ▁ ▁P ump ▁cli ps ▁ ▁P ump ▁cli ps ▁are ▁bad ges ▁that ▁are ▁attached ▁to ▁hand p umps ▁in ▁pub s ▁to ▁show ▁which ▁c ask ▁al es ▁are ▁available . ▁In ▁addition ▁to ▁the ▁name ▁of ▁the ▁be er ▁served ▁through ▁the ▁p ump , ▁they ▁may ▁give ▁other ▁details ▁such ▁as ▁the ▁bre wer ' s ▁name ▁and ▁alco hol ic ▁strength ▁of ▁the ▁be