This looks like a pants size chart for American guests. The unit of measurement is inches:

According to the order you provided, the translation contents are as follows.

Waist slack (@ topedge) 19 1/2 Waist slack measurement (along the fixed edge)

Waist slack (@ btmiedge) 2 1 waist slack measurement (along the bottom edge)

Belt height 1 5/8 waist height (waist width)

Position of high hip circumference (top edge of Frm) 4 Position of high hip circumference (measured downward from the fixed edge of waist)

High hip girth 23 High hip girth size

Position of low hip circumference (upper edge of Frm) 8 Position of low hip circumference (measured downward from upper edge of waist).

Low hip circumference 24 1/2 low hip circumference

Curtain/Length (frm top edge) 6 3/8 Length of the placket (measured downward from the waist top edge)

Zipper opening 3 front 3/4 front zipper opening length (not shown, uncertain)

Zipper length 4 1/2 zipper length

Protrusion (front top edge) 10 3/4 front wavelength (front crotch length, from the top edge of waist)

Back rise (frm top edge) 18 1/2 back wave length (back crotch bending length, from waist top)

Saddle @ 2" 9 has no picture material and cannot be translated accurately.

Hip level/depth (frm top edge) 10 1/2 Hip low position (leg root position) is away from the top edge.

Thigh (@ widest) 15 1/4 Leg root circumference (thickest part)

Mid-thickness position (from crotch @ seam) 6 3/4 Mid-leg circumference (low crotch, downward along seam)

Medium thickness 12 3/4 Mid-leg circumference

Knee position (from crotch @ seam) 13 1/2 knee circumference (from crotch down along seam)

Knee 10 3/4 knee circumference

Legopening 1 1 foot circumference

Internal seam length of internal seam 33

I hope the above translation is helpful to you. If you can have the guest's graphic information, you will get more accurate and detailed Chinese meaning. thank you