LGV named Verbessen ie improved I believe.
Has meteor style seal mount
Ours has HW seal fitted now
working well

reminds me need to check that adapter. Home fabricated construction so may be unraveling.

The later of these 55s on right has synthetic seal on screwed fitment and slight differences in trigger sear to the older on left.
Don't know what sealing is on the older one. May have look tomorrow.

Triggers and interlocks are a bit fiddly to dismantle/reassemble but, to me, very effective.