60 Minute Microcassette Tapes- 6 Pack TDK Microcassettes provide consistent, reliable performance in telephone answering machines and microcassette recorders. Strengthened, high quality ferric oxide tape provides maximum durability and excellent audio clarity. 

TDK Microcassettes are designed to withstand repeated recording and frequent playback in answering machines and microcassette 
recorders. Less scrupulous brands cut corners on microcassette materials and manufacturing, which can lead to early tape failure. 
If you want to set it and forget it, go with TDK Microcasettes.