▁served ▁through ▁that ▁hand p ump . ▁ ▁The ▁handle ▁of ▁a ▁hand p ump ▁is ▁often ▁used ▁as ▁a ▁symbol ▁of ▁c ask ▁ale . ▁ ▁This ▁style ▁of ▁be er ▁has ▁continued ▁fer ment ation ▁and ▁uses ▁por ous ▁and ▁non - por ous ▁p eg s , ▁called ▁sp iles , ▁to ▁respectively ▁release ▁and ▁retain ▁the ▁g ases ▁generated ▁by ▁fer ment ation ▁and ▁thus ▁achieve ▁the ▁optim um ▁level ▁of ▁carbon ation ▁in ▁the ▁be er . ▁ ▁In ▁the ▁ 1 9 7 0 s ▁many ▁bre wer ies ▁were ▁keen ▁to ▁replace ▁c ask ▁condition ed ▁ale ▁with ▁k eg ▁versions ▁for ▁financial ▁benefit , ▁and ▁started ▁to ▁dis gu ise ▁k eg ▁t aps ▁by ▁ad or ning ▁them ▁with ▁cos met ic ▁hand ▁p ump ▁handles . ▁This ▁practice ▁was ▁opposed ▁as ▁fra ud ul ent ▁by ▁the ▁Camp aign ▁for ▁Real ▁Ale ▁and ▁was ▁dis cont in ued . ▁ ▁Sw an ▁neck ▁ ▁A ▁sw an ▁neck ▁is ▁a ▁cur ved ▁sp out . ▁ ▁This ▁is ▁often ▁used ▁in ▁conj unction ▁with ▁a ▁spark ler ▁- ▁a ▁no zz le ▁containing ▁small ▁holes ▁- ▁fitted ▁to ▁the ▁sp out ▁to ▁aer ate ▁the ▁be er ▁as ▁it ▁enters ▁the ▁glass , ▁giving ▁a ▁fro th ier ▁head ; ▁this ▁presentation ▁style ▁is ▁more ▁popular ▁in ▁the ▁north ▁of ▁England ▁than ▁in ▁the ▁south . ▁ ▁Spark ler ▁A ▁spark ler ▁is ▁a ▁device ▁that ▁can ▁be ▁attached ▁to ▁the ▁no zz