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Parker 8-166 backup ring envelope (uncut)

Parker 8-166 backup ring envelope (uncut): ID 6.768 in (171.91 mm), OD 6.940 in (176.28 mm), thickness 0.053 in (1.35 mm); for the AS568 -166 O-ring

Exact dimensions. True size, no tolerance added. Threads are plain cylinders at the major diameter.

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Dimensions

dash8-166
ID (in)6.768
OD (in) = ID + 2W6.940
radial width W (in)0.086
thickness T (in)0.053
ID (mm)171.91
OD (mm)176.28
T (mm)1.35
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From the full sheet

Backup rings for AS568 O-rings (Parker 8-xxx Parbak, 8-004 to 8-475): ID, OD, width and thickness per dash size: every size, notes, mating features and sources. What are the ID, OD and thickness of an 8-214 (or 8-110, 8-325) backup ring for an AS568 O-ring?

Other sizes