To improve the sealing performance and O-ring life span, the battery compartment O-ring gland design has been changed from a crushed gland to a radial gland. Identification of the new radial cap can be made by observing the differences in the following table:
New: Radial Cap
- Radial gland design
- O-ring seals before computer turns on
- Sealing NOT dependent on torque applied to battery cap
- The compression on the O-ring is set by the gland groove diameter
- Petrel computer marked with “RC” under strap
- NERD computer marked with “RC” above battery compartment
SRI PART NUMBER: 21021-01

Note Screw Head Height and O-Ring Colour

Note O-Ring Groove Style

Machine Screw: Pan Head #4-40 x 1/4” Torx T10
Old: Crushed Cap
- Crushed O-ring gland design
- O-ring starts to seal as computer turns on
- Sealing dependent on torque applied to cap
- As the cap is tightened the O-ring is compressed into a cone shaped gland
- Tighter the cap is the more the O-ring is crushed/compressed
SRI PART NUMBER: 21021

Note Screw Head Height and O-Ring Colour

Note O-Ring Groove Style

Plastite Screw 48-2 Flat Head #4-20 x 3/8” Torx T8