The actual pronunciation of these sounds in PIE is not certain. One current idea is that the "palatovelars" were in fact simple velars, i.e. , while the "plain velars" were pronounced farther back, perhaps as uvular consonants, i.e. . If the labiovelars were just labialized forms of the "plain velars", they would then have been pronounced but the pronunciation of the labiovelars as would still be possible in uvular theory, if the satem languages first shifted the "palatovelars" and then later merged the "plain velars" and "labiovelars". See for more support of this theory.