Greencity Acquisition Corporation (NASDAQ:GRCY) announced this morning that it has signed a non-binding letter of intent with Bopai Construction Technology and plans to enter into a definitive agreement to combine after a period of due diligence.

Shanghai-based Bopai specializes in 3D architectural printing and has 43 patents around the sustainable building construction. This includes 3D concrete printing, 3D rammed earth printing and it can use these to build structural columns, ring beams, floor slabs as well as water and electrical infrastructure.

Greencity is the oldest SPAC in SPACInsider‘s “Searching” column, having IPO’d in July 2020. It will remain there if and until its discussions with Bopai result in a definitive agreement. Only three SPACs in circulation that are in the “Announced” column listed earlier than Greencity and the oldest among them – Brilliant (NASDAQ:BRLI) – only by a month.

As a result of being so long in the tooth, Greencity has extended its transaction deadline three times and redemptions have whittled its trust down to $6.5 million. Those remaining shares are to vote next Tuesday, April 25, whether to further extend its deadline to October 28.

The redemption deadline for that vote is 5 pm ET today, so this announcement very much fits the category of a teaser.

Greencity cannot be accused of dangling a target from the monetarily sexiest sector, however. The 12 companies that completed SPAC transactions from the 3D printing and advanced materials spaces over the past 10 years last closed with a median share price of  $2.09.

Bopai does not appear to have an English-language web presence and the parties have thus far released very little information on its operations. But, it appears that its business crosses over with the construction sector in ways that might gain it consideration as a proptech player.

But, the 13 de-SPACs from that sector are having an even rougher time in the current market waters with a median share price below $1 and only one trading above $4.