In the 1960s, if you wanted to get an audio copy of the Bible into a closed country, you'd need to carry a suitcase-sized, portable reel-to-reel machine along with at least 50 pounds of reels. In the 1970s, you would use a rectangular cassette player plus a case of 50 cassettes. In the 1980s, your choice of cassette players could vary from a large boom box to be carried on your shoulder to a small unit that could be attached to your belt. In the 1990s, you would cary a portable compact disc player with about 60 cds. In the 2000s, you could carry a small mp3 player loaded with the entire bible. And today, if you are looking to get audio Bibles into a closed country, you can bring a one inch square mini sd card player with a 2 GB card capable of holding over 600 hours of the Bible and teaching programs! That's a great technological advancement for the Great Commission.
(Photo of Ray Alary, President of TWR-Canada holding a mini sd card player)