Red rubber sleeve stoppers used as substrates for the sex pheromone of the codling moth,Laspeyresia pomonella(L.), produced a 1st order loss curve (k = 1.09 × 10−3/h corresponding to a half-life of 26.5 days); rubber bands produced a complex loss curve; and polyethylene caps allowed extensive chemical degradation after a few days. In field trapping tests, a release rate of 1.25 μg/h produced the highest catches. Sleeve stoppers baited with 1.5 mg of attractant/stopper had virtually maximum attractiveness for a month and would be ideal for mass trapping during this period. Sleeve stoppers baited with 5 mg of attractant/stopper may be used for survey since the rate loss curve indicates they will be more attractive than the old survey bait of 10 ♀ after as much as 4.4 mo (5 half-lives).