Bronze wire wraps a tin-plated steel core for the Martin Marquis MA150S medium tension acoustic strings. A soft silk wrap on the ball ends helps prevent wear on your guitar's bridge and end plate.
| Note | Gauge (in.) | Material |
| E/1st | .013 | Plain steel |
| B/2nd | .017 | Plain steel |
| G/3rd | .026 | 80/20 Bronze |
| D/4th | .035 | 80/20 Bronze |
| A/5th | .045 | 80/20 Bronze |
| E/6th | .056 | 80/20 Bronze |