The upright regulation guides assist with the measurements for: 5 Blow distance 46mm - 50mm, 5 Damper lift 14mm - 18mm, 5 Set off/let off 2mm - 6mm, 5 Checking distances 14mm -18mm, Made in an ivory colour to enable easy reading when in working in an action, Individually marked for ease of use. The guides are designed in a stable thermoplastic polymer made strictly from renewable resources generated from biodegradable materials like cornstarch.