Did you miss Face Slots? They’re back.

With TaylorMade’s RSi irons, released in 2015, the company introduced a never-before-seen, ultra-visible technology on its club faces. Two polymer-filled slots — one on the heel, one on the toe — were added to help raise ball speeds on off-center hits.

Face Slots have been added to TaylorMade’s new M1 and M2 irons.

With the company’s 2016 game-improve release, the M2 and M2 Tour irons, Face Slots went away. But for TaylorMade’s 2017 release of the irons bearing the same name, the forgiveness-based, Face-Slot technology is back.

According to TaylorMade, Face Slots are most effective on shots hit high and on the toe of the club face, an area where the majority of golfers contact their irons shots. The Face Slots couple with several new design features to further increase distance and forgiveness compared to the 2016 M2 irons.

TaylorMade’s M2 (left) and M1 irons use Speed Pockets, slots in the sole that make the club faces more flexible.

Also new for 2017 are TaylorMade’s M1 irons, the first edition of irons with that name. They replace the M2 Tour irons in the company line, a compact distance iron that we’ve spotted in the bags of PGA Tour players, who use them as long-iron and hybrid replacements.

The M1 name in TaylorMade’s M-Series is synonymous with more compact heads, clubs that serious golfers tend to prefer. Keeping with that theme, the M1 irons have smaller bodies, thinner soles and thinner top lines, but are made with many of the same technologies as the 2017 M2 irons.

Learn more about each of the new iron designs below.

2017 M2 irons

TaylorMade’s new M2 irons are made with 33 percent thinner top lines, meaning they will look sleeker at address than their predecessors. They also have a 7 percent shallower blade height, helping to lower center of gravity (CG) for a higher launch.

Speed Pockets in the 4, 5, 6 and 7 irons, which were used in previous iterations to increase ball speeds on off-center hits, were made 20 percent deeper to improve the flexibility of the club faces. They help improve ball speed on center strikes, but more importantly they promote more ball speed on off-center hits than their predecessors.

As seen in the 2016 M2 irons, the 2017 M2 irons also have fluted hosels to save weight, except the six-sided flutes are now wider and thinner, saving an additional 2 grams that was used to lower the CG of the iron heads. With what may be music to club fitters’ ears, TaylorMade added a slot at the hosel bend, allowing the clubs to be bent easier for less restriction on loft and lie angle adjustments.

As with the M1 and M2 drivers, the M2 irons have a “Geocoustic” design to improve sound and feel. For the irons, that means there’s a vibration-dampening badge behind the face, and a rib structure tucked below the topline that creates better sound and feel.

The M2 irons are also available with a sand wedge (54 degrees) that’s designed specifically for bunker play, rather than full shots from grass. It uses more bounce to help golfers more easily move the club through sand. A 59-degree lob wedge has a low-bounce design to perform better from tight lies.

The M2 irons (4-LW) will sell for $799 with steel REAX HL 88 shafts by FST (S and R flexes) and $899 with M2 REAX graphite shafts (S, R, A, L flexes). They will be available Jan. 27, 2017.

M1 Irons

Although TaylorMade’s M1 irons are made to be more compact and sleeker than the M2 irons, they use tungsten in the toes of the long irons (3-7) to ensure forgiveness is not sacrificed. The addition of tungsten in the M1 irons allowed TaylorMade to nearly center CG in the irons — about 1 millimeter from center, according to TaylorMade — from heel-to-toe, and drop CG lower in the head for a higher launch and a greater MOI (moment of inertia, a measure of forgiveness).

The M1 irons also have a fluted hosel to save weight, but it’s used only on the under portion of the hosel, effectively blocking the weight-saving design from a golfer’s view at address.

Compared to the 2017 M2 irons, the M1 irons have many of the same technologies, including a “Geocoustic” design for better sound and feel. They also have Face Slots and Speed Pockets in their soles (also used in the 3-7 irons) to improve forgiveness on off-center strikes.

TaylorMade’s M2 (left) and M1 irons at address.

The leading edges and sole widths are thinner on the M1 irons when compared to the M2 irons, helping improve turf interaction for better players who are likely to have slightly shallower angles of attack.

The M1 irons (3-PW) will be available on March 1, 2017, and will come stock with True Temper’s XP95 steel shafts ($999) or Mitsubishi Rayon’s Kuro Kage Silver graphite shafts ($1,199). Additional shafts options are also available for no upcharge.

Related

• 12 Important Changes to the 2017 TaylorMade M1 and M2 Drivers
• TaylorMade 2017 M1 Fairway Woods and Hybrids: What you need to know
• TaylorMade 2017 M2 Fairway Woods and Hybrids: What you need to know
• TaylorMade makes big claims about new TP5 and TP5x golf balls