Made from balck Nylon

4 standoffs and 4 washers per pack

6 sizes to choose from, ID x OD x Length

*4mm x 8mm x 5mm (height 0.196" about 3/16 inch)

*4mm x 8mm x 10mm (height 0.394" about 3/8 inch)

*4mm x 8mm x 15mm (height 0.591" about 5/16 inch)

*5mm x 10mm x 5mm (height 0.196" about 3/16 inch)

*5mm x 10mm x 10mm (height 0.394" about 3/8 inch)

*5mm x 10mm x 15mm (height 0.591" about 5/16 inch)

*8mm x 12mm x 20mm (height 20mm is about 13/16)

*8mm x 12mm x 30mm (height 30mm is about 1-1/5 inch) 

Washers are stainless, 4mm ID washers with the 4mm ID stand offs and 5mm ID with the 5mm stand offs

Washer measurements: 4mm are (4.4ID x 12 OD x 0.95mm thick) 5mm are (5.4 x 15 x 1mm thick)

8mm ID standoffs come with 5mm washers (5.4 x 15 x 1mm thick)