Perhaps his most notable innovation during his Pittsburgh tenure came during the season, when the Pirates became the first team to permanently adopt batting helmets on both offense and defense. These helmets resembled a primitive fiberglass "miner's cap". This was the mandate of Rickey, who also owned stock in the company producing the helmets. Under Rickey's orders, all Pirate players had to wear the helmets both at bat and in the field. The helmets became a permanent feature for all Pirate hitters, but within a few weeks the team began to abandon their use of helmets on defense, partly because of their awkwardly heavy feel. Once the Pirates discarded the helmets on defense, the trend disappeared from the game.