For the Z-RAM 88g-to-88g ON/OFF adapter with pressure gauge, support recommends a separate 88g capsule-mounted shoulder rest rather than simply refitting the unchanged original stock. The specific alternative is the black 88g capsule shoulder rest shown below.
A thread match is not a stock-clearance check
The 88g-to-88g adapter with gauge sits between the capsule and the marker. Its listed body length is 7 cm, and its diameter including the gauge is 5.5 cm. Those dimensions describe an additional component that the surrounding stock arrangement has to accommodate; they are not a measurement of the complete installed length.
The current compatibility description names Umarex HDX68/TX68 in the 40J/pressure-housing configuration, MPX, and the 88g / 16x1.5 interface. That identifies the gas connection and listed marker context. It does not, by itself, establish clearance inside an original stock.
The shoulder rest attaches to the capsule
The recommended rest is made from 3D-printed polymer with a TPU grip. It fits directly on a standard 88g CO₂ capsule, not on an HPA bottle. This is a different support arrangement from expecting the original stock to slide back over the added adapter.
The rest offer supplies one shoulder rest; the marker, valve and capsule remain separate. The adapter offer supplies one ON/OFF adapter with gauge and no capsule. They perform different jobs: the adapter is part of the gas connection, while the rest provides shoulder support.
Do not confuse the adapter with the pressure housing
The separate HDX68/TX68 pressure-housing description says that the shoulder stock remains usable. That statement concerns the pressure housing—not the full arrangement after adding this separate ON/OFF adapter with its gauge.
For a purchase around the gauge adapter, treat the capsule support as its own item rather than assuming the original stock is already covered. If retaining a particular original stock is essential, have that exact rear arrangement checked before choosing the parts.
The adapter and the separate capsule support
ON/OFF adapter 88g|88g | HDX68 | MPX | with display
The 88g-to-88g ON/OFF adapter with pressure gauge: black anodized aluminum, 7 cm long and 5.5 cm across including the gauge. No capsule is supplied.
View the gauge adapter
Shoulder rest | 88g capsule | BUTTSTOCK | BLACK | stylish design
The exact black 88g capsule shoulder rest named by Z-RAM support. Polymer with TPU grip; for the capsule itself, not an HPA bottle.
View the 88g shoulder restAnother 88g capsule-stock design
This short introduces another Z-RAM 88g capsule-stock design. It provides broader context for capsule-mounted shoulder support; the product card above is the specific polymer/TPU rest named in the support answer.
▶ Play on YouTube🚀💥 Ultimate 88g co2 Shoulder Stock – Z-RAM Buttstock for 88g co2 capsules for FSC HDR68 HDR50 HDP50😎
Channel: Z-RAM
An overview of the HDX68/TX68 range
For an optional look at the HDX68/TX68 range, this short includes adapters and pressure housings among the parts discussed. It is a range overview, not a test of original-stock clearance.
▶ Play on YouTubeTuning for #Umarex #HDX68 #TX68 #co2gun #homedefense #co2airgun #airgun #airsoft #lesslethal #zram 🚀
Channel: Z-RAM
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