SHS M90 Main Spring - The CQB Specialist for High-Speed Performance

When you are playing at tight - indoor UK venues - staying safely under the site limit while maintaining a lightning-fast trigger response is the priority. The SHS M90 is specifically engineered to provide a reliable - lower-velocity output that keeps you well within the 328-350 FPS bracket. Designed for players who value "Rate of Fire" over raw range - this spring allows your motor to cycle with minimal resistance - making it the perfect heart for a dedicated CQB "Stinger" build.

Key Features and Performance

• Stress-Relieved Spring Steel - Precisely coiled to prevent the "sagging" common in stock springs - ensuring your FPS remains stable for every game day.
• Lightweight Compression Profile - The thinner wire gauge allows for a much faster gearbox cycle - putting less strain on your 7.4v or 11.1v batteries.
• Non-Linear Progressive Wind - Designed to be softer at the start of the stroke - which saves your sector gear from unnecessary impact and prolongs the life of your shell.
• Polished Exterior Surface - Reduces internal drag against the piston wall - ensuring that even at high speeds - your internals stay cool and efficient.
• Standard AEG Dimension - Fully compatible with almost every Tokyo Marui spec rifle - including popular platforms like the Specna Arms - G&G - and ASG series.

The "Pro" Take

The SHS M90 is the "go-to" for the high-speed tech. Because it requires very little torque to pull back - you can pair this with high-speed (13:1 or 12:1) gears to achieve a truly terrifying Rate of Fire without drawing massive amounts of current. It is also the safest "Insurance Policy" for your gearbox - if you have a V2 shell that you are worried about cracking - the M90 significantly reduces the forward impact force - keeping your rifle in the game for years rather than months.

UK Spec and Site Performance

In the UK - "CQB" sites like "The Department" or "Bunker 51" often have strict 328 FPS limits (1.0 Joule). An M90 is the most reliable way to hit those numbers. In a build with a 200mm to 280mm barrel - you can expect the M90 to sit comfortably between 290 and 315 FPS with 0.20g BBs.

This "Safety Margin" is brilliant for UK players because it accounts for "Creep" or slight variances in site chronographs - ensuring you never have to walk back to the car because your gun is shooting "hot." While it won't reach as far across a woodland clearing as an M110 - it excels in urban environments where your engagements are under 30 metres. We recommend using 0.20g or 0.25g BBs with this setup to maintain a high muzzle velocity and a flat trajectory through those tight doorways and windows.

Friendly FAQ

Is this the best spring for indoor sites?
Absolutely. Most indoor sites in the UK have a 350 FPS hard-cap - but many prefer you to be closer to 300-315 FPS for safety. The M90 is the industry standard for meeting these requirements.

Will this work with my "out of the box" AEG?
Yes! Most factory AEGs come with an M100 or M110. Swapping to an M90 is a simple way to "downgrade" your power for indoor use while actually increasing your battery life and semi-auto speed.

Can I use an 11.1v LiPo with an M90?
You can - but be aware of "Premature Engagement" (Piston timing issues). If your gun has a very high rate of fire - you may need to "short stroke" a tooth off your gears to keep everything in sync with such a fast-returning spring.

Does this spring come with a warranty?
Like all airsoft internal components - the warranty covers manufacturing defects. However - because it is a "wear and tear" part - its lifespan depends on how hard you run your rifle!