This latest Duo provides enhanced sound quality, one- or two-message capability, and a quick and easy way to change overlays. Find multiple uses with the one-message option, or use the duo mode for simple sequencing, multiple-choice selections, or language exploration. 10 seconds per message. Note: There are several ways to make overlays for this product: use Go Talk Overlay software; write words on blank overlay template with a marker; cut/paste pictures or symbol cues onto an overlay template; place velcro on each square and add a texture cue.