There you go:
www.groworganic.com/item_PBR650_SnailBarr_Copper_Barrier_3_x_20_.html?welcome=T&theses=4979255

Can't be arsed looking more.
( Esme Weatherwax I swear on my tash it's daycent hash, Tue 16 Jun 2009, 18:37, archived)

no no no
it's because it stops them reaching 88 miles per hour
( spacefish bong!, Tue 16 Jun 2009, 19:16, archived)