This price has not changed since 2026-10-01 12:08 UTC. It reflects the last observed trade rather than current market value, and this page is excluded from our sitemap for that reason.
Community price on backpack.tf: 11.0–12.0 keys, last changed 2026-08-09 (3mo ago). The live quote above, 13.2 keys, is 20% higher and last moved 1mo ago. They are different measures: the quote is what traders and bots are asking and bidding on the classifieds right now, and it moves for thousands of items every day; the community price is a suggestion accepted by vote, which changes only when someone argues it should. A quote well away from the vote is usually a price that is about to be re-argued. Community prices from backpack.tf, read under an hour ago.
Steam Market asking price: $40.09 — the lowest of 2 listings for the Massed Flies effect when we looked on 2026-11-04 01:39 UTC (1d ago). This is what a seller is asking, not what anything sold for. Steam pays out in Steam wallet funds, not cash, and Valve takes roughly 15% at the till — so asking prices there run well above the 13 keys, 13.22 ref shown above, which comes from the keys-and-metal market on backpack.tf. The two are different markets and are never blended. Steam lists the item as “Unusual Bonk Helm”, with no effect in the name — the effect comes from the individual listing.
Price history
Interactive chart. Press the left and right arrow keys to move along the series, Home or End to jump to either end, Escape to clear.
The key axis converts at today's rate. Prices are recorded in metal, so a line that is flat in keys followed the key rate rather than standing still.
| Observed (UTC) | Sell | Buy |
|---|---|---|
| 25 SEP 2025 · 03:29 UTC | 10.2 keys | 8.32 keys |
| 30 SEP 2025 · 20:14 UTC | 10.1 keys | 8.30 keys |
| 19 OCT 2025 · 19:44 UTC | 9.22 keys | 8.30 keys |
| 25 OCT 2025 · 16:01 UTC | 8.78 keys | 7.90 keys |
| 10 NOV 2025 · 00:02 UTC | 9.10 keys | 8.19 keys |
| 10 JUN 2026 · 04:30 UTC | 11.6 keys | 8.25 keys |
| 15 JUN 2026 · 16:10 UTC | 11.4 keys | 9.99 keys |
| 26 JUN 2026 · 11:12 UTC | 7.19 keys | 6.25 keys |
| 11 JUL 2026 · 20:44 UTC | 7.75 keys | 6.73 keys |
| 4 AUG 2026 · 11:12 UTC | 10.5 keys | 9.17 keys |
| 11 AUG 2026 · 03:11 UTC | 10.8 keys | 9.47 keys |
| 27 AUG 2026 · 12:08 UTC | 13.5 keys | 11.7 keys |
| 30 AUG 2026 · 18:09 UTC | 13.0 keys | 11.3 keys |
| 31 AUG 2026 · 10:09 UTC | 12.9 keys | 11.2 keys |
| 3 SEP 2026 · 14:08 UTC | 12.6 keys | 10.9 keys |
| 4 SEP 2026 · 06:08 UTC | 12.6 keys | 11.0 keys |
| 4 SEP 2026 · 18:08 UTC | 12.6 keys | 10.9 keys |
| 5 SEP 2026 · 18:08 UTC | 12.5 keys | 10.9 keys |
| 6 SEP 2026 · 06:09 UTC | 12.5 keys | 10.9 keys |
| 6 SEP 2026 · 18:08 UTC | 12.5 keys | 10.9 keys |
| 7 SEP 2026 · 18:08 UTC | 12.8 keys | 11.1 keys |
| 8 SEP 2026 · 10:08 UTC | 13.1 keys | 11.4 keys |
| 10 SEP 2026 · 12:08 UTC | 11.6 keys | 10.1 keys |
| 14 SEP 2026 · 06:08 UTC | 13.2 keys | 11.5 keys |
| 14 SEP 2026 · 14:07 UTC | 13.0 keys | 11.3 keys |
| 21 SEP 2026 · 16:09 UTC | 12.2 keys | 10.6 keys |
| 22 SEP 2026 · 00:08 UTC | 12.4 keys | 10.8 keys |
| 22 SEP 2026 · 04:09 UTC | 12.4 keys | 10.8 keys |
| 22 SEP 2026 · 06:09 UTC | 12.4 keys | 10.8 keys |
| 22 SEP 2026 · 10:08 UTC | 12.5 keys | 10.9 keys |
| 23 SEP 2026 · 22:10 UTC | 12.2 keys | 10.6 keys |
| 24 SEP 2026 · 02:09 UTC | 13.0 keys | 11.3 keys |
| 26 SEP 2026 · 20:09 UTC | 12.8 keys | 11.1 keys |
| 27 SEP 2026 · 20:09 UTC | 13.0 keys | 11.3 keys |
| 1 OCT 2026 · 12:08 UTC | 13.2 keys | 11.5 keys |
| 7 OCT 2026 · 13:09 UTC | 12.5 keys | 10.9 keys |
| 10 OCT 2026 · 23:09 UTC | 13.5 keys | 11.8 keys |
| 17 OCT 2026 · 01:07 UTC | 12.0 keys | 10.4 keys |
| 20 OCT 2026 · 21:11 UTC | 13.7 keys | 11.9 keys |
| 23 OCT 2026 · 05:12 UTC | 13.7 keys | 11.9 keys |
Price history in numbers
53 readings since 25 Sep 2025Over the last 30 days the Massed Flies Bonk Helm's sell price ranged from 12.0 keys to 13.7 keys and is up 9.7% after 5 moves. Over a year it ranged from 7.08 keys to 13.7 keys (up 50.8%). Today's 13.7 keys sits at the top of its range: the lowest we have recorded is 7.08 keys (7 Jul 2026) and the highest 13.7 keys (23 Oct 2026). The price has moved 52 times since we began recording it — about once every 8 days.
| Window | Low | High | Change | Moves | Readings |
|---|---|---|---|---|---|
| 30 days | 12.0 keys | 13.7 keys | +9.7% | 5 | 6 |
| 90 days | 10.8 keys | 13.7 keys | +26.6% | 39 | 40 |
| a year | 7.08 keys | 13.7 keys | +50.8% | 47 | 48 |
Details
| SKU | 106;5;u12 |
|---|---|
| Last price change | 2026-10-01 12:08 UTC |
| Key rate when recorded | 63.00 ref |
Same effect, other items
the effect across the catalogue| Item | Value | Updated |
|---|---|---|
| 1,200 keys | 12mo ago | |
| 600 keys | 12mo ago | |
| 581 keys | 12mo ago | |
| 500 keys | 12mo ago | |
| 481 keys | 12mo ago | |
| 470 keys | 12mo ago | |
| 325 keys | 12mo ago | |
| 321 keys | 1mo ago | |
| 309 keys | 1mo ago | |
| 236 keys | 2mo ago |
Other effects on the Bonk Helm
same item, different effect| Item | Value | Updated |
|---|---|---|
| 593 keys | 1mo ago | |
| 420 keys | 12mo ago | |
| 409 keys | 3mo ago | |
| 352 keys | 1mo ago | |
| 188 keys | 2mo ago | |
| 185 keys | 3mo ago | |
| 185 keys | 1mo ago | |
| 173 keys | 2mo ago | |
| 168 keys | 4mo ago | |
| 159 keys | 3mo ago |
Priced similarly
across the catalogue| Item | Value | Updated |
|---|---|---|
| 13.2 keys | 1mo ago | |
| 13.5 keys | 1mo ago | |
| 13.0 keys | 1mo ago | |
| 13.2 keys | 1mo ago | |
| 13.1 keys | 2mo ago | |
| 13.3 keys | 2mo ago | |
| 13.2 keys | 1mo ago | |
| 13.2 keys | 1mo ago |