The Milsig/Valken M17 HEAT CORE bolt-bumper offer contains three reinforced silicone bumpers, each 3 mm thick. Choose it when the cushioning bumper is the part you need; choose the separate M17 HE O-Ring Kit when you need its assortment of named O-rings. The similar HEAT CORE wording does not make the two packs interchangeable.
What the reinforced bumper is designed to do
The bumper's job is cushioning. Z-RAM describes its two-component industrial-grade silicone design as more durable than the original and associates it with smoother, quieter cycling. Those are the reasons to consider this particular replacement, beyond simply having three spares in the package.
Its 3 mm thickness and Shore A26 hardness identify the offered bumper. When comparing it with an existing part, use the exact M17 bumper identity as well as its material and thickness.
Compare the two HEAT CORE service purchases
| Offer | What the pack covers | When it is the useful choice |
|---|---|---|
| HEAT CORE Bolt Bumpers | Three reinforced silicone bumpers of the same type | You need the cushioning bumper or want spares of that part |
| M17 HE O-Ring Kit | Five O-rings across four named entries | You need the mixed selection for the listed Heatcore and regulator positions |
The O-ring kit contains one AC Main O-ring (Heatcore 15), one AC-to-Reg O-ring (Heatcore 11), two Bolt-to-AC Bumper O-rings (Heatcore 13), and one Regulator O-ring (Regulator 2). The numbers in parentheses are the listing's component labels, not millimeter sizes.
The phrase “Bumper O-rings” in the kit deserves attention: it identifies the two Heatcore 13 rings in that assortment. It does not describe a second pack of the reinforced 3 mm silicone bumpers. Match the complete part name to your replacement need rather than choosing by the word “bumper” alone.
Read material figures in their proper context
Z-RAM lists heat resistance up to 250 °C and reports testing up to 2,000 PSI HPA outlet pressure. These describe the seller's material and product-test claims; they are not an M17 temperature or pressure setting. The useful purchase details remain the specified bumper, construction and fit.
The bumper offer names Milsig/Valken M17. The O-ring kit separately names Milsig M17 G3 and Valken M17. Keep each part's stated fit attached to that offer; one product's generation coverage does not automatically extend to another.
Choose around the part that needs attention
A cushioning replacement and a seal assortment answer different service needs. Seals help keep gas contained, and seal condition can affect consistency, but a symptom alone does not tell you which of these packs is required. Once the affected part is identified, the comparison above lets you buy the focused bumper pack or the mixed O-ring selection without treating them as a compulsory bundle.
For a broader explanation of matching model, generation and component before ordering, see how to choose compatible Z-RAM parts.
Choose the M17 service part you need
3x HEAT CORE BOLT BUMPER | Milsig Valken M17
Three reinforced HEAT CORE cushioning bumpers for Milsig/Valken M17. Each is 3 mm thick, made from two-component silicone with listed Shore A26 hardness.
View the bumper three-pack
Milsig / Valken M17 HE O-Ring Kit
The separate HE O-Ring Kit for Milsig M17 G3/Valken M17 contains five rings across four named entries. Choose it for those seal positions, rather than as another pack of reinforced silicone bumpers.
Compare the HE O-Ring KitGeneral Z-RAM viewing: explore the product categories
After choosing your M17 service part, this short shop introduction gives a broader view of Z-RAM's own-brand categories. It is general shop viewing, separate from the bumper and O-ring comparison.
▶ Play on YouTubeThe Ultimate Shop for RAM Tuning Parts: Ammo, Valves, Chambers, and More HDR50 TR68 FSC TCP
Channel: Z-RAM
General Z-RAM viewing: other marker families
The second introduction turns to the wider model range, including Umarex T4E and FSC/TCP parts. It offers another route through the shop if you also own other markers.
▶ Play on YouTubeFind the Best Umarex T4E Parts at Z-Ram.net . HDR68 TR50 HDP50 TS68 Pepperball First Strike
Channel: Z-RAM
Important Legal Notice
Laws and regulations governing the purchase, possession, installation, modification, and use of the products described on this page vary by country, state, and local jurisdiction and may change. Before purchasing, installing, modifying, or using any product, you are responsible for confirming that it is permitted in your location and for your intended purpose. Product availability or delivery does not mean that purchase, possession, installation, modification, or use is lawful in your jurisdiction. Z-RAM does not provide legal advice, and the information on this page must not be treated as legal advice. If you are unsure, contact the competent local authority or a qualified legal professional.