Proto-Concept C05 Irons Specifications

Full factory loft, lie and length chart for the Proto-Concept C05 irons, 2020–2024.

Years produced
2020–2024
Category
Players Distance Irons
Construction
pocket cavity (forged SAE8655 face welded to S25C body)
Material
SAE8655 chromium-molybdenum steel face, S25C carbon steel body
Set makeup
5–PW

Loft, lie & length chart

Standard men's steel-shaft specifications for the Proto-Concept C05 irons.
ClubLoft (°)Lie (°)Length (in)Bounce
5256138.253
62861.537.754
7326237.255
83662.536.756
9406336.257
PW4563.535.758

Lofts and lies are the factory standard build. Individual clubs may differ if they have been bent, re-shafted or re-gripped during their life.

About the Proto-Concept C05

The C05 was the tour pocket cavity in PROTOCONCEPT's original C-series, released in 2020 as part of the first iron range from the brand the Endo forging house and the Golf Partner retail group established in 2019. A forged SAE8655 chromium-molybdenum face varying between 2.4 and 2.7 mm in thickness is welded to an S25C carbon steel body over a milled pocket cavity, trading blade purity for ball speed while sharing the C01's loft ladder - a 32-degree 7-iron and 45-degree pitching wedge - so the two blend into combo sets. Heads are sold component-style, 5-PW, assembled to order in Japan or the USA; Patty Tavatanakit and Lydia Ko helped put the brand on the international map. Lengths below are the manufacturer's recommended steel assembly lengths; PROTOCONCEPT publishes face progression rather than offset, so that key is omitted. The C05TP superseded it in 2024.

Related models

Frequently asked questions

What is the loft of a Proto-Concept C05 7-iron?

The Proto-Concept C05 7-iron has a loft of 32 degrees, with a 62-degree lie and a 37.25-inch recommended steel length.

Is the Proto-Concept C05 forged?

The body is forged S25C carbon steel and the face is a separately forged SAE8655 chromium-molybdenum plate, 2.4 to 2.7 mm thick, welded over a milled pocket cavity.

Can the C05 be combined with other Proto-Concept irons?

Yes. The original C01, C03, C05 and C07 share the same loft ladder club-for-club, and PROTOCONCEPT designed them to be blended into combo sets.

Finding a used set

The Proto-Concept C05 ran from 2020 to 2024 and is no longer in production, so the used market is the only source. Search eBay, 2nd Swing, Golf Avenue and the PGA Tour Superstore trade-in listings, and check the loft and lie against the chart above before buying — sets this age have often been bent from standard.

Data compiled from:
  • protoconceptgolf.com C05 product page (archived 29 November 2022) — manufacturer spec table used here: lofts 25/28/32/36/40/45, lies 61-63.5, bounce 3-8, FP 3.8-4.8 mm, SAE8655 nickel-chrome-plated face on S25C body, plus recommended-assembly steel lengths 38.25 to 35.75 inches (common to all listed steel shafts)
  • shop.torquegolf.com Proto Concept C05 listing — independent corroboration of the full loft/lie/bounce/FP chart and the pocket-cavity construction
  • mygolfspy.jp 'Know Your Japanese Brands' (September 2021) — C05 and C07 on the Japanese market from 2020, face thickness varying 2.4-2.7 mm, brand established 2019 by Endo and Golf Partner
  • protoconceptgolf.com press release announcing the C05TP (2024) — dates the successor used for year_discontinued

Last reviewed 2026-07-29. Spot an error? [email protected]