<?xml version="1.0" encoding="UTF-8"?><informationTable xmlns="http://www.sec.gov/edgar/document/thirteenf/informationtable" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"><infoTable><nameOfIssuer>American Tower Corp</nameOfIssuer><titleOfClass>CL A</titleOfClass><cusip>03027X100</cusip><value>16826550</value><shrsOrPrnAmt><sshPrnamt>97500</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>97500</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>Antero Resources Corp</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>03674X106</cusip><value>13793000</value><shrsOrPrnAmt><sshPrnamt>325000</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>325000</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>CECO Environmental Corp</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>125141101</cusip><value>33872839</value><shrsOrPrnAmt><sshPrnamt>568527</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>568527</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>Coterra Energy Inc</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>127097103</cusip><value>20205500</value><shrsOrPrnAmt><sshPrnamt>575000</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>575000</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>Forum Energy Technologies Inc</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>34984V209</cusip><value>13198500</value><shrsOrPrnAmt><sshPrnamt>225000</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>225000</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>Manitowoc Co Inc/The</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>563571405</cusip><value>15872950</value><shrsOrPrnAmt><sshPrnamt>1362485</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>1362485</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>Mistras Group Inc</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>60649T107</cusip><value>16561655</value><shrsOrPrnAmt><sshPrnamt>1120545</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>1120545</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>Quanex Building Products Corp</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>747619104</cusip><value>15475207</value><shrsOrPrnAmt><sshPrnamt>861169</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>861169</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>Range Resources Corp</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>75281A109</cusip><value>13413129</value><shrsOrPrnAmt><sshPrnamt>296882</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>296882</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>Ranger Energy Services Inc</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>75282U104</cusip><value>29076947</value><shrsOrPrnAmt><sshPrnamt>1696438</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>1696438</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>RPC Inc</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>749660106</cusip><value>17784217</value><shrsOrPrnAmt><sshPrnamt>2511895</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>2511895</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>Team Inc</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>878155308</cusip><value>1195532</value><shrsOrPrnAmt><sshPrnamt>75002</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>75002</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable><infoTable><nameOfIssuer>Unisys Corp</nameOfIssuer><titleOfClass>COM</titleOfClass><cusip>909214306</cusip><value>6706800</value><shrsOrPrnAmt><sshPrnamt>3240000</sshPrnamt><sshPrnamtType>SH</sshPrnamtType></shrsOrPrnAmt><investmentDiscretion>SOLE</investmentDiscretion><votingAuthority><Sole>3240000</Sole><Shared>0</Shared><None>0</None></votingAuthority></infoTable></informationTable><!-- tableEntryCount=13 tableValueTotal=213982826 -->
