Used Mackenzie MacFi-mp 40. Mpeg Digital Audio Record / play system. Messages are user recordable. The MacFi Mp 40 offers up to 99 messages and 40 minutes of MP3 audio. Uses non-volatile flash memory, eliminating the need for battery backup. Its small size and industrial construction, the lack of moving parts make it ideal for automatic unattended operations in harsh environmental or mobile conditions. Used part. Please browse our Bus Parts Superstore for all of your shuttle bus, church bus and RV parts needs.