near the top of legs 54 a and 54 b respectively proximate to arms 52 a and 52 b respectively leg grooves 66 a and 66 b provide another mechanical stop for when lid 30 shown in fig6 rotates by engaging nibs 37 a and 37 b shown in fig4 respectively the first mechanical stop described above is tabs 58 a and 58 b engaging front edge 174 of lid 30 thereby limiting rotation between spring 50 and lid 30 further arms 52 a and 52 b have overhangs 59 a and 59 b respectively overhangs 59 a and 59 b are simply the result of substantially rectangular grooves on the interior lateral portions of arms 52 a and 52 b and will be explained in further detail with respect to fig7 c as described above with respect to fig6 spring 50 has curved surfaces 64 a and 64 b to accommodate nozzle 72 fig7 b is a front perspective view of spring 50 in a cocked position in this position the shaft of tongue 56 is bent and the tip of tongue 56 is configured between colinear arms 52 a and 52 b the tapered shaft and tapered slot 55 of tongue 56 enable tongue 56 to be fitted between arms 52 a and 52 b by being narrower than the gap between arms 52 a and 52 b further the shaft of tongue 56 may be forcibly squeezed narrower if needed to fit.