Complete O-ring kits that make servicing easy Horizon is now utilizing the AS568A O-Ring standard used by the O-Ring industry in order to bring a standardized approach to the pool and spa industry. The current active Horizon part number for an o-ring is 90-423-5xxx, where xxx represents the AS568A designation. This designation ranges from -001 thru -932, in order of smallest to largest first by cross section then by diameter. Please see substitute item number under “Quick info” for the current SKU for this item.
Exploded parts diagrams: This part is shown as the Cartridge Filter, StaRite Posi-Flo II, PTM135; the Cartridge Filter,Pentair/StaRite Posi-Flo II,PTM50/70/100 exploded parts diagrams.
🔧 Cartridge Filter, StaRite Posi-Flo II, PTM135 – exploded parts diagram

The numbered parts below make up this assembly. Parts we stock are linked – click any to view.
| No. | Part |
|---|---|
| – | Ro-Kit 272, Sta-Rite Posi-Flo II Filter ◀ this part |
| – | Tool, Socket, Quad-Side A/Solar Side B |
| – | Tool, Clamp Knob Socket, 4-Lobe, w/1/4" Socket Bit Adapter |
| 17 | Clamp Ring Nut, Pentair Sta-Rite, Plastic |
| 16 | Tank Body, Pentair Sta-Rite PosiFlo PTM50, PTM70 |
| 15 | O-Ring, 9-1/2" ID, 1/4" Cross Section, Generic |
| 14 | Clamp Ring Nut, Pentair Sta-Rite, Brass |
| 13 | 16-102-W003K13 |
| 12 | Tank Base, Pentair Sta-Rite PosiFlo/DE Separation, w/Plugs |
| 11 | Clamp Ring, Pentair Sta-Rite PosiFloII,w/o Nut, Bottom |
| 10 | 16-102-W003K10 |
| 9 | Air Bleed Filter, Pentair Sta-Rite PosiFlo |
| 7 | Plug, Pentair Sta-Rite PosiFlo, Upper Tank Body |
| 8 | 16-102-W003K8 |
| 6 | Upper Tank Body, Pentair Sta-Rite PosiFlo/DE Separation |
| 5 | 16-102-W003K5 |
| 4 | O-Ring, 10-1/2" ID, 1/4" Cross Section, Generic |
| 3 | 16-102-W003K3 |
| 2a | O-Ring, 1/2" ID, 3/32" Cross Section, Generic |
| 2 | 16-102-W003K2 |
| 1a | Pressure Gauge Screen, Pentair Sta-Rite |
| 1 | Pressure Gauge, Pentair StaRite,1/4"mpt,0-60psi,Bottom Mount |













