Coalescing Filter: Replaces the 40 micron filter for both moisture and particulate filtration. (Type 51SSAR & Type 51SSAF only) P/N 010-312-000 Non-Relieving: Used in applications where it is desirable to relieve pressure downstream and not at the regulator. Non-relieving regulators should not be used for low or no flow applications. Socket Head Build Screw: Socket head build screws are provided in place of phillips drive screws. 5 Micron Filter: Replaces the 40 micron filter for more complete air filtration. (Except Type 51SSR) P/N 836-000-002 Mounting Bracket: 316 Stainless Steel bracket for side mounting. P/N 607-000-128 Pressure Gauge: Dual scale (psi / kPa) 21⁄2" (63mm) gauges. Ranges include 0-60 psi (0-410 kPa), 0-100 psi (0-690 kPa) and 0-200 psi 0-1400 kPa). When specified with regulator, the correct range will be supplied. Tamper Resistant Cover: A 316 stainless steel hexagonal cover placed over the adjusting screw and threaded onto the bonnet of the regulator with a wrench, prevents ordinary hand adjustments. Low Bleed Diaphragm: (Soft Relief Seat): Used in applications where it is desirable to minimize the standard bleed rate of the regulator while maintaining the ability to relieve excess pressure at the regulator. (Bleed rate is reduced from less than 6 SCFH (2.8 LPM) to less than 0.1 SCFH (0.05 LPM).