Check whether Bulletproof Fitness attachments fit your power rack. Every rack spec below is quoted from the manufacturer’s own page. Where a maker doesn’t publish a number, this tool says so instead of guessing.
1. Your rack
Measure across the hole, not the pin. A caliper, or a drill bit from a set you know, settles it in a minute.
What this checks, and what it cannot
This tool answers one question: will a given Bulletproof Fitness attachment physically mount to your rack? It does that by comparing three published numbers — your upright size, your hole diameter, and the inside width between your front uprights — against what Bulletproof states each attachment needs.
Every rack specification it uses is quoted from the manufacturer’s own page. Where a maker does not publish a number, the tool says so rather than filling the gap. That matters more than it sounds: rack specifications are one of the most frequently misreported figures on the internet, and a wrong hole diameter is the difference between a pin that slides home and a $900 attachment that arrives and does not fit.
What it cannot tell you is whether the result is safe. Fit and safety are different questions. A bolted 3×3 rack with 11-gauge uprights and an unbolted 2×2 rack with thin-wall tubing can both take the same pin, and only one of them should carry a loaded carriage. The tool flags that distinction where it can, but it cannot see your rack, your floor, or how well the bolts went in.
Want the general rundown of how rack attachment compatibility works across brands, not just Bulletproof? Read the Power Rack Attachment Compatibility Guide, or check every attachment brand at once with the Rack Attachment Fit Checker.
The three numbers this tool checks
This tool compares three numbers against what Bulletproof publishes for each attachment: your rack’s upright size (3×3, 2×3 or 2×2), the hole diameter drilled through it, and the inside width between your front uprights. Bulletproof sells the Isolator with pins for 1/2, 5/8, 3/4 and 1 inch holes, which covers most of the market but not all of it.
Width is the one people forget
Some Bulletproof products are width-sensitive in ways the upright size will not warn you about. The Isolator Pullover attachment fits racks with 39 to 45 inches of inside width. The VTS has been tested to a maximum of 43 inches of inside width. Outside those ranges the pin size is irrelevant, because the geometry does not close.
Measure it before you buy, and measure between the inner faces at the height the attachment will actually sit. Some racks are not perfectly square, and a rack that has been moved, dragged, or assembled on an uneven floor can be out by enough to matter.
Bolted down changes what is safe, not what fits
Bulletproof states that the VTS must be mounted to a firmly mounted rack. That is not a fit requirement, it is a stability one. A rack-mounted carriage puts load in directions a power rack was never designed for: forward, outward, and in the case of a belt squat or pullover, upward on one side.
If your rack is free-standing and not weighed down, an attachment can fit perfectly and still be a bad idea. The tool has a field for this because the honest answer to “will it work” changes depending on it, even when the answer to “will it bolt on” does not.
When the answer is “needs checking”
A check before ordering or not listed result means one of the deciding numbers isn’t published by your rack’s manufacturer, or Bulletproof doesn’t name your rack specifically. If you’d rather not guess, the second tab lets you enter your measurements directly and skip the rack database entirely — your tape measure is a primary source, and a product page isn’t always kept current. For tips on measuring hole diameter and upright size yourself, see the Power Rack Attachment Compatibility Guide.